Organs Sentence Examples
See, my organs cannot be damaged and my metabolism processes liquor much faster than yours.
The docs put you in a coma for over a week in order to transplant half your organs.
The sense organs are typically ocelli, never otocysts.
The internal organs are shown as seen by transmitted light.
The essential Molluscan organs are, with these exceptions, uniformly well developed.
She continued to exercise her vocal organs mechanically, as ordinary children do.
The nervous system and sense organs are highly developed.
The body-cavity also contains the socalled phagocytic organs.
Sclerostomum armatum, y, X about 31, opened to show the phagocytic organs.
The eggs of the female give rise to embryos within the body of the mother; her other organs undergo a retrogressive change and serve as food for the young, until the body-wall only of the mother remains as a brown capsule.
AdvertisementBeyond this simple condition the visual organs of the Hydromedusae do not advance, and are far from reaching the wonderful development of the eyes of Scyphomedusae (Charybdaea).
Brooks regards these organs as sensory, serving for the sense of balance, and representing a primitive stage of the tentaculocysts of Trachylinae; Linko, on the other hand, finding no nerve-elements connected with them, regards them as digestive (?) in function.
In this way the medusa sinks from an independent per sonality to an organ of the polyp-colony, becoming a so-called medusoid gonophore, or bearer of the reproductive organs, and losing gradually all organs necessary for an independent existence, namely those of sense, locomotion and nutrition.
The direct method of medusa-budding only differs from the polyp-bud by its greater complexity of parts and organs.
To sum up, the entocodon is a precocious formation of the umbrella, closing over to protect the organs in the umbrellar cavity.
AdvertisementBalfour put forward the view that the polyp was the more primitive type, and that the medusa is a special modification of the polyp for reproductive purposes, the result of division of labour in a polypcolony, whereby special reproductive persons become detached and acquire organs of locomotion for spreading the species.
When fully developed the medusa is characterized by the sense organs being composed entirely of ectoderm, developed independently of the tentacles, and innervated from the sub-umbral nerve-ring.
These organs are supported by cuplike structures of the perisarc, termed nematophores, regarded as modified hydrothecae supporting the specialized polyp-individuals.
In addition to the stems bearing cups, there are found vesicles associated with them, which have been interpreted as gonothecae or as floats, that is to say, air-bladders, acting as hydrostatic organs for a floating polyp-colony.
In the first place the cormus has been regarded as a single individual and its appendages as organs.
AdvertisementThus the umbrella of the Siphonula became the protocodon, and its manubrium, the axis or stolon, which, by a process of dislocation of Organs, escaped, as it were, from the sub-umbrella through a cleft and became secondarily attached to the ex-umbrella.
Thus he says that nature fashions organs in the order of their necessity, the first being those essential to life.
The superiority of animals to plants and metals in the possession of special organs of sense is connected with the greater complexity and heterogeneity of their structure.
Thus he suggests that man has not eyes of a microscopic delicacy, because he would receive no great advantage from such acute organs, since though adding indefinitely to his speculative knowledge of the physical world they would 1 Yet he leaves open the question whether the Deity has annexed thought to matter as a faculty, or whether it rests on a distinct spiritual principle.
Notwithstanding the origin of organs, it still for a certain time, by reason of its want of an internal bony skeleton, remains worm and mollusk, and only later enters into the series of the Vertebrata, although traces of the vertebral column even in the earliest periods testify its claim to a place in that series."
AdvertisementIt is not true, for example, that a fish is a reptile arrested in its development, or that a reptile was ever a fish; but it is true that the reptile embryo, at one stage of its development, is an organism which, if it had an independent existence, must be classified among fishes; and all the organs of the reptile pass, in the course of their development, through conditions which are closely analogous to those which are permanent in some fishes.
Nevertheless, doubleedged as is the argument from rudimentary organs, there is probably none which has produced a greater effect in promoting the general acceptance of the theory of evolution.
The conception of evolution is being applied more rigidly to the comparative anatomy of organs and systems of organs.
Such a condition has been termed, with regard to the group of animals or plants the organs of which are being studied, archecentric. The possession of the character in the archecentric condition in (say) two of the members of the group does not indicate that these two members are more nearly related to one another than they are to other members of the group; the archecentric condition is part of the common heritage of all the members of the group, and may be retained by any.
Especially in the case of manifest adaptations, organs possessed by creatures far apart genealogically may be moulded into conditions that are extremely alike.
The third and fourth oecumenical synods (Ephesus, 43 1; Chalcedon, 451) were primarily tribunals for the trials of Nestorius and Dioscorus; it was secondarily that they became organs of the universal episcopate for the definition of the faith, or legislative assemblies for the enactment of canons.
The arches bear on the convex outer side the delicate arborescent gills, and on the concave inner side develop a membranous septum with vermicular perforations, a special sifting or filtering contrivance through which the water absorbed by the mouth has to pass before reaching the respiratory organs of the branchial apparatus.
He defined them as possessing radial instead of bilateral symmetry, and as apparently destitute of nervous system and sense organs, as having the circulatory system rudimentary or absent, and the respiratory organs on or coextensive with the surface of the body; he included under this title and definition five classes, - Echinodermata, Acalepha, Entozoa, Polypi and Infusoria.
In Caulerpa the imitation of a higher plant by the differentiation of fixing, supporting and assimilating organs (root, stem and leaf) from different branches of the single cell is strikingly complete.
In the first place there is a differentiation of fixing organs, which in forms living on.
The hydrom strand has in most cases no connection with the leaves, but runs straight up the stem and spreads out below the sexual organs or the foot of the sporogonium.
In the more highly developed series, the mosses, this last division of labor takes the form of the differentiation of special assimilative organs, the leaves, commonly with a midrib containing elongated cells for the ready removal of the products of assimilation; and in the typical forms with a localized absorptive region, a well-developed hydrom in the axis of the plant, as well as similar hydrom strands in the leaf-midribs, are constantly met with.
The gametophyte, which bears the sexual organs, is either a free-living thallus corresponding in degree of differentiation with the lower liverworts, or it is a mass of cells which always remains enclosed in a spore and is parasitic upon the sporophyte.
These are special organs, ?Iydathodes.
The cells concerned, like all secreting organs, have abundant protoplasm with large nuclei, and sometimes, in addition, part of the cell-wall is modified as a filter.
The xylem and phloem are nearly always found in close association in strands of various shapes in all the three main organs of the sporophyteroot, stem and leafand form a connected tissue-system running through the whole body.
Hence such tracheae are only laid down in organs whose growth in length has ceased.
A peculiar modification of periderm is formed by the phellogen in the submerged organs (roots or stems) of many aquatic or marsh-loving plants.
Filicales and Gymnosperms, and known as the Cycadofihices, a group in which, curiously enough, the reproductive organs remained undiscovered for some time after the anatomy of the vegetative organs was sufficiently well known to afford clear evidence of their true affinities.
In this matter, differentiation has proceeded very differently in animals and plants respectively, no nerves or sense organs being structurally recognizable.
It was formerly the custom to regard as parasites all those pants which inserted roots or root-like organs into the tissues of other plants and absorbed the contents of the latter.
The food so absorbed passes to the outer cortical mycellum, and from this tc the inner hyphae, which appear to be the organs of the interchangi of substance, for they are attracted to the neighborhood of thi nuclei of the cells, which they enter, and iii which they form agglom erations of interwoven filaments.
This group is represented by the erepsin of the pancreas and other organs.
This is not perhaps so evident in the case of axial organs as it is in that of leaves and their modifications, but even in them it can be detected to a certain extent.
Cylindrical organs may exhibit similar phenomena.
This continuous change of position has been called circumnutation, and is held to be universal in all growing cylindrical organs.
It can, however, be seen in adult organs, though instances are less numerous.
We find on further investigation that these two conditions are traceable to different parts of the organs concerned.
Even the root tip, which shows a certain differentiation into root cap and root apex, cannot be said to be a definite sense organ in the same way as the sense organs of an animal.
The sensitive cells must clearly be influenced in some way by weightnot the weight of external organs but of some weight within them.
We have spoken of the absence of structural differentiation in the sense organs.
The power of response is seen most easily in the case of young growing organs, and the parts which show the motor mechanism are mainly the young growing cells.
Nor is it only in growing organs that the rhythm can be observed, for many plants exhibit it during a much longer period than that of growth.
The extraordinary forms, colors and textures of the true galls have always formed some of the most interesting of biological questions, for not only is there definite co-operation I between a given species of insect and of plant, as shown by the facts that the same insect may induce galls of different kinds on different plants or organs, while different insects induce different galls on the same plante.g.
Pythium, Peronospore, Completoria, Vol utelta, Botrytis, &c. That such overturgescence should lead to the bursting of fleshy fruits, such as gooseberries, tomatoes and grapes, is not surprising, nor can we wonder that fermentation and mould Fungi rapidly spread in such fruits; and the same is true for bulbs and herbaceous organs generally.
NecrosisA number of diseases the obvious symptoms of which are the local drying up and death of tissues, in many cases with secondary results on organs or parts of organs, may be brought together under this heading.
He showed that all the organs of plants are built up of cells, that the plant embryo originates from a single cell, and that the physiological activities of the plant are dependent upon the individual activities of these vital units.
They are spherical, oval, fusiform, or rod-like, and are always found in the cytoplasm, never in the cell-sap. They appear to be permanent organs of the cell, and are transmitted from one cell to another by division.
Organs which respond to the mechanical stimulus of contact are found to possess special contrivances in certain of their cells(I) sensitive spots, consisting of places here and there on the epidermal cells where the wall is thin and in close contact with protoplasmic projections.
The earliest scientific result of the study of plants was the recognition of the fact that the various parts of the body are associated with the performance of different kinds of physiological work; that they are, in fact, organs discharging special functions.
The origin of the organography of the present day may be traced back to Aristotle, who described the parts of plants as organs, though very simple ones.
Pure Morphology.Thus it became apparent that the mans and various organs of plants are, for the most part, different forms of a small number of members of the body, which have been distinguished as follows, without any reference to function.
In a differentiated body the stem (caulome) is an axis capable of bearing leaves and (directly or indirectly) the proper reproductive organs.
The root is an axis which never bears either leaves or the proper reproductive organs (whether sexual or asexual) of the plant.
It is urged that the various parts are, as a matter of fact, organs; and that it is therefore inadmissible to ignore their functions, as is done in the foregoing definitions.
Thus, in a phanerogam, the sepals, petals, stamens and foliage-leaves all come under the category leaf, though some are parts of the perianth, others are spore-bearing organs (sporophylls), and others carry on nutritive processes.
When two organs can be traced along the same line of descent to one primitive form, that is when they are found to be mono phyletic, their homology is complete; when, however, they are traceable to two primitive forms, though these forms belong to the same morphological series, they are polyphyletic and therefore only incompletely homologous.
All organs performing the same function and showing similar adaptations are said to be analogous or homoplastic, whatever their morphological nature may be; hence organs are sometimes both homologous and analogous, sometimes only analogous.
Metamorphosis.It has already been pointed out that each kind of member of the body may present a variety of forms. For example, a stem may be a tree-trunk, or a twining stem, or a tendril, or a thorn, or a creeping rhizome, or a tuber; a leaf may be a green foliage-leaf, or a scale protecting a bud, or a tendril, or a pitcher, or a floral leaf, either sepal, petal, stamen or carpel (sporophyll); a root may be a fibrous root, or a swollen tap-root like that of the beet or the turnip. All these various forms are organs discharging some special function, and are examples of what Wolff called modification, and Goethe metamorphosis.
The sepals are generally organs for the protection of the flower-bud; the petals, for attracting insects by their conspicuous form and color; the foliage-leaves, for the assimilation of carbon dioxide and other associated functions.
But this phylogenetic differentiation of the organs was not what Wolff and Goethe had in mind; what they contemplated was an ontogenetic change, and there is abundant evidence that such changes actually occur.
Evolution means the gradual development of highly organized from lowly organized forms; that is, of forms in which the physiological division of labor is more complete, from those in which it is less complete; of forms possessing a variety of organs, from forms possessing but few.
Differentiation means the development and the specialization as organs of various parts of the body.
For instance, the animal traps of carnivorous plants (Drosera, Nepenihes, &c.) did not, presumably, originate as such; they began as organs of quite another kind which became adapted to their present function in consequence of animals having been accidentally caught.
Yet thrcughout they agree in the essential structure of their floral organs.
If land forms may be compared to organs, the part they serve in the economy of the earth may, without straining the term, be characterized as functions.
Consequently only a few of the original extensor muscles have been preserved, but these are much modified into very independent organs, notably the extensor metacarpi radialis longus, the ext.
The results are as interesting from a morphological point of view (showing the subtle and gradual modifications of these organs in their various adaptations), as they are sparse in taxonomic value, far less satisfactory than are those of the hind-limb.
The last nerve which contributes to the ischiadic plexus leaves the spinal column in most birds either between the two primary sacral vertebrae, or just below the hindmost of them, and sends a branch to the pubic portion which is composed of post-ischiadic nerves, partly imbedded in the kidneys, and innervates the ventral muscles between the tail and pubis, together with those of the cloaca and copulatory organs.
Gadow, " Remarks on the Cloaca and on the Copulatory Organs of the Amniota."
In many beetles the hindwings are reduced to mere vestiges useless for flight, or are altogether absent, and in such cases the two elytra are often fused together at the suture; thus organs originally intended for flight have been transformed into an armour-like covering for the beetle's hind-body.
These stridulating organs were mentioned by C. Darwin as probable examples of the action of sexual selection; they are, however, frequently present in both sexes, and in some families also in the larvae.
It is remarkable that these organs are found in similar positions in genera belonging to widely divergent families, while two genera of the same family may have them in different positions.
Stridulating organs among beetle-larvae have been noted, especially in the wood-feeding grub of the stag-beetles (Lucanidae) and their allies the Passalidae, and in the dung-eating grubs of the dor-beetles (Geotrupes), which belong to the chafer family (Scarabaeidae).
The function of the stridulating organs just described is presumably to afford means of recognition by sound.
The luminous organs of these beetles consist of a specialized part of the fat-body, with an inner opaque and an outer transparent layer.
As organs of the Police central government there are further, the ispravniki, chiefs of police in the districts into which the governments are divided.
The result of this policy of repression, associated as it was with gross incompetence and corruption in the organs of the administration, was the rapid spread of the revolutionary movement, which gradually permeated the intelligent classes and ultimately " Tolstoi - observed that that was argument and reason, and that he paid no attention to them; he only guided himself (he said) by sentiment, which he felt sure told him what was good and right!
The organs of government seemed paralysed by the repudiation of the principle on which their authority was based, and the empire to be in danger of falling into complete anarchy.
The knees are of a soft spongy texture and act as breathing organs, supplying the roots with air,, which they would otherwise be unable to obtain when submerged.
In the interior organs there are indications of a compensating accumulation of blood, such as swelling of the spleen, engorgement (very rarely rupture) of the heart, with a feeling of oppression in the chest, and a copious flow of clear and watery urine from the congested kidneys.
Wing-covers and hind-wings are alike absent, and the latter are represented by a pair of little knobbed organs, the halteres or balancers, which have a controlling and directing function in flight.
It is customary to divide the Orthorrhapha into the two divisions Nematocera and Brachycera, in the former of which the antennae are elongate and in a more or less primitive condition, as described above, while in the latter these organs are short, and, as already explained, apparently composed of only three joints.
For the appreciation of the sounds made by these stridulators, the ants are furnished with delicate organs of hearing (chordotonal organs) in the head, in the three thoracic and two of the abdominal segments and in the shins of the legs.
Sharp to hold the maggots between their mandibles and induce them to spin together the leaves of trees from which they form their shelters, as the adult ants have no silk-producing organs.
Fielde show that an ant follows her own old track by a scent exercised by the tenth segment of the feeler, recognizes other inmates of her nest by a sense of smell resident in the eleventh segment, is guided to the eggs, maggots and pupae, which she has to tend, by sensation through the eighth and ninth segments, and appreciates the general smell of the nest itself by means of organs in the twelfth segment.
The floral structure is so curious that perhaps less attention has been paid to the vegetative organs than the peculiarities of their organisation demand.
The internal organs are largely repeated metamerically, in correspondence with the external metamerism.
The setae are organs of locomotion, though their large size and occasionally jagged edges in some of the Polychaeta suggest an aggressive function.
Goodrich, endorsed by Lankester, led to the opinion that under the general morphological conception of "nephridium" were included two distinct sets of organs, viz.
D, Optical section of a branch of organs are present to the number of a single pair per somite, and are commonly present in the majority of the segments of the body, failing often among the Oligochaeta in a varying number of the anterior segments.
It is not clear, for example, to which category it is necessary to refer the excretory organs of Arenicola, or Polynoe.
Both series of organs consist essentially of a ciliated tube leading from the coelom to the exterior.
Both series of organs grow back centrifugally from the funnel.
It has been ascertained that the nephridia of Oligochaeta are preceded in the embryo by a pair of delicate and sinuous tubes, also found in the Hirudinea and Polychaeta, which are larval excretory organs.
Thus the nephridia, in this case at least, are a part of the coelom and are not shut off from it by a layer of peritoneum, as are other organs which lie in it, e.g.
The paired disposition of these organs is the prevalent one among the Oligochaeta, and occurs in all of twelve out of the thirteen families into which the group is divided.
There is a spacious cavity surrounding the gut and containing also bloodvessels, and to some extent the generative organs.
The city's manufactures include glass, brick, tile, carriages and wagons, agricultural implements, pianos and organs and cigars.
Violently attacked by the Boulangist organs, L'Intransigeant and La France, he won a suit against them for libel, and in 1889 he contested the 18th arrondissement of Paris with General Boulanger, who obtained a majority of over 2000 votes, but was declared ineligible.
Further, as the country became more consolidated and the central government extended its authority over economic affairs, new regulations came into force, new organs of government appeared, which were sometimes in conflict, sometimes in harmony, with the existing system, and it becomes for a time far more difficult to obtain a clear view of the actual working of economic institutions.
The chief interest of the place centres in its brine springs which are largely impregnated with carbonic acid gas and oxide of iron, and are efficacious in chronic catarrh of the respiratory organs, in liver and stomach disorders and women's diseases.
The (primitively) right-hand organs of the complex thus become lefthand, and vice versa.
When the shell is sinistral the asymmetry of the organs is usually reversed, and there is a complete situs inversus viscerum, the direction of the spiral of the shell corresponding to the position of the organs of the body.
The pallial cavity, with its organs, is by this torsion moved up the right side of the larva to the dorsal surface, and thus the left organs become right and vice versa.
The gonad has no accessory organs and except in Neri- tidae no duct, but discharges into the right kidney.
The existence of two renal organs in Patella, and their relation to the pericardium (a portion of the coelom), is important.
Pectinibranchia.-In this order there is no longer any trace of bilateral symmetry in the circulatory, respiratory and excretory organs, the topographically right half of the pallial complex having completely disappeared, except the right kidney, which is FIG.
As in all such introand e-versible organs, eversion of the Gastropod proboscis is effected by pressure communicated by the muscular body-wall to the liquid contents (blood) of the body-space, accompanied by the relaxation of the muscles which directly pull upon either the sides or the apex of the tubular organ.
No opening into the body-cavity has been made; the organs which lie in the coiled visceral hump show through its transparent walls.
Accessory organs are rarely found on the genital ducts, but occur in Paludina, Cyclostoma, Naticidae, Calyptraeidae, &c. Mandibles usually present.
Many Opisthobranchia have by a process of atrophy lost the typical ctenidium and the mantleskirt, and have developed other organs in their place.
The variety of special developments of structure accompanying the atrophy of typical organs in the Opisthobranchia and general degeneration of organization is very great.
As so great a part of the whole surface of the kidney lies adjacent to external surfaces of the body, the remaining part which faces the internal organs is small; it consists of the left part of the under surface; it is level with the floor of the pericardium, and lies over the globular mass formed by the liver and convoluted intestine.
The Pulmonata are, like the other Euthyneura, hermaphrodite, with elaborately developed copulatory organs and accessory glands.
Such cannulated cells are characteristic of the nephridia of many worms, and the organs thus formed in the embryo Limnaeus are embryonic nephridia.
Bonaparte's selection gave general satisfaction, as also did the personnel of the Council of State (divided into five sections for the chief spheres of government) and of the other organs of state.
The compound eyes of insects resemble so closely the similar organs in Crustaceans that there can hardly be reasonable doubt of their homology, and the primitively appendicular nature of the eyes in the latter class suggests that in the Hexapoda also they represent the appendages of an anterior (protocerebral) segment.
Paired processes on the eighth and ninth abdominal segments may be specialized as external organs of reproduction, but these are probably not appendages.
Elaboration in the form of the feelers, often a secondary sexual character in male insects, may result from a distal broadening of the segments, so that the appendage becomes serrate, or from the development of processes bearing sensory organs, so that the structure is pinnate or feather-like.
The legs, wings and other organs of the trunk receive their nerves from the thoracic and abdominal ganglia, and the fusion of several pairs of these ganglia may be regarded as corresponding to a centralization of individuality.
In connexion with the central nervous system there are usually numerous organs of special sense.
The nature of these organs is described in the article Arthropoda.
Auditory organs of a simple type are present in most insects.
These consist of fine rods suspended between two points of the cuticle, and connected with nerve-fibres; they are known as chordotonal organs.
It is said that 13,000 such olfactory organs are present on the feeler of a wasp, and 40,000 on the complex antennae of a male cockchafer.
Organs of similar type on the maxillae and epipharynx appear to exercise the function of taste.
B, Section through compound eye (after Miall and Denny); C, organs of smell in cockchafer; (after Kraepelin); D, a, b, sensory pits on cercopods of golden-eye fly; c, sensory pit on palp of stone-fly (after Packard); E, sensory hair (after Miall and Denny); F, ear of long-horned grasshopper; a, Front shin showing outer opening and air-tube; b, section (after Graber); G, ear of locust from within (after Graber).
Accessory glands are commonly present in connexion both with the male and the female reproductive organs.
They have chiefly been studied in the female, and form the sting and ovipositor, organs peculiar to this sex.
With regard to the internal organs, we need only say that transformation occurs in an essentially similar manner, by means of a development from centres distributed in the various organs.
In the case of the common drone-fly, Eristalis tenax, the individual, from a sedentary maggot living in filth, without any relations of sex, and with only unimportant organs for the ingestion of its foul nutriment, changes to a creature of extreme alertness, with magnificent powers of flight, living on the products of the flowers it frequents, and endowed with highly complex sexual structures.
In the metabolic Hexapoda the resting pupal instar shows externally the wings and other characteristic imaginal organs which have been gradually elaborated beneath the larval cuticle.
But in none of these latter cases have the wings to be changed from a position inside the body to become external and actively functional organs.
The difference between the nymph or false pupa and the true pupa is that in the latter a whole stage is devoted to the perfecting of the wings and body-wall after the wings have become external organs; the stage is one in which no food is or can be taken, however prolonged may be its existence.
These organs, thus acquired during the lifetime of the individual, must have been in some way acquired during the evolution of the class.
It is almost impossible to believe that any species of insect that has for a long period developed the wings outside the body could change this mode of growth suddenly for an internal mode of development of the organs in question, for, as we have already explained, the two modes of growth are directly opposed.
If it should be objected that the wings so developed would be rudimentary, and that there would be nothing to encourage their development into perfect functional organs, we may remind the reader that we have already pointed out that imperfect wings of Exopterygota do, even at the present time under certain conditions, become perfect organs; and we may also add that there are, even among existing Endopterygota, species in which the wings are usually vestiges and yet sometimes become perfectly developed.
But it may perhaps be considered improbable that organs like the wings, having once been lost, should have been reacquired on the large scale suggested by the theory just put forward.
He was quite aware of the taxonomic value of the vocal organs of some groups of birds, presently to be especially mentioned, and he had himself ascertained the presence and absence of caeca in a not inconsiderable number of groups, drawing thence very justifiable inferences.
In all these species he found the vocal organs to differ essentially in structure from those of other birds of the Old World, which we now call Passerine, or, to be still more precise, Oscinian.
Indeed he was so much prepossessed in favour of a classification based on the structure of the digestive organs that he could not bring himself to consider vocal muscles to be of much taxonomic use, and it was reserved to Johannes Muller to point out that the contrary was the fact.
Carrying on the work from the anatomical point at which he had left it, correcting his errors, and utilizing to the fullest extent the observations of Keyserling and Blasius, to which reference has already been made, Muller, though hampered by mistaken notions of which he seems to have been unable to rid himself, propounded a scheme for the classification of this group, the general truth of which has been admitted by all his successors, based, as the title of his treatise expressed, on the hitherto unknown different types of the vocal organs in the Passerines.
On the other hand, he declares that the American rodstart, Muscicapa, or, as it now stands, Setophaga ruticilla, when young, has its vocal organs like the rest - an extraordinary statement which is worthy the attention of the many able American ornithologists.
These laws, as formulated by him, are that (1) there is a coincidence of form of the anterior palatal and of the cranium in birds of the same order; (2) there is a likeness between the anterior palatal bones in birds of the same order; (3) there are relations of likeness 1 The title of the English translation is Johannes Muller on Certain Variations in the Vocal Organs of the Passeres that have hitherto escaped notice.
To these succeeded forms where the down had developed into body feathers for warmth, not flight, whilst the fore-limbs had become organs of prehension, the hind-limbs of progression.
Among the leading and more distinctive items were printing and publishing ($21,023,855 in 1905); sugar and molasses refining ($ 1 5,74 6, 547 in 1900; figures not published in 1905 because of the industry being in the hands of a single owner); men's clothing (in 1900, $8,609,475, in 1905, $11,246,004); women's clothing (in 1900, $3,258,483, in 1905, $5,705,470); boots and shoes (in 1900, $3,882,655, in 1905, $5,575,927); boot and shoe cut stock (in 1905, $5, 211, 445); malt liquors (in 1900, $7,518,668, in 1905, $6,715,215); confectionery (in 1900, $4,455,184, in 1905, $6,210,023); tobacco products (in 1900, $3,504,603, in 1905, $4,59 2, 698); pianos and organs ($3,670,771 in 1905); other musical instruments and materials (in 1905, $231,780); rubber and elastic goods (in 1900, $3,139,783, in 1905, $2,887,323); steam fittings and heating apparatus (in 1900, $2,876,327, in 1905, $3,354, 020); bottling, furniture, &c. Art tiles and pottery are manufactured in Chelsea.
The making of the Chickering pianos goes back to 1823, and of Mason & Hamlin reed organs to 1854; these are to-day very important and distinctive manufactures of the city.
During pairing he thrusts the tip of these organs into the seminal vesicles of the female and the eggs are fertilized as they pass out of the oviduct.
It is only at the final moult that the sexual organs are mature, the two sexes being alike in the earlier stages of growth.
It is believed that the males of these species signal to their females by means of the sound these organs emit.
So far as is known, however, only the large spiders belonging to this group possess this special means of defence, and in many other species this is accompanied by highly-developed stridulating organs resembling those of rattlesnakes and scorpions in function.
Graber turned their attention to the detailed investigation of some one species or to special points in the structure of some particular organs, using for the elucidation of their subject the ever-improving microscopical methods of research.
Thus as life is transcendent and yet immanent in body, and mind in brain, and both utilize their organs, so God, transcendent and immanent, uses the course of nature for His own ends; and the emergence both of life and mind in that course of nature evidences such a divine initiative as is assumed in the recognition of the possibility of miracles.
As central organs we have to note the brain-lobes and the longitudinal lateral cords which form one continuous unsegmented mass of fibrous and cellular nerve-tissue.
It stretches forward as far as the brain, and in Carinella is again continued in front of it, whereas in the Heteronemertines the innervation of the anterior extremity of the head, in front of the brain, takes the form of more definite and less numerous branching stems. The presence of this plexus in connexion with the central stems, sending out nervous filaments amongst the muscles, explains the absence, in Pro-, Mesoand Heteronemertines, of separate and distinct peripheral nerve stems springing from the central stems innervating the different organs and body-regions, the only exceptions being the L.N.
In addition to the nerves starting from the brain-lobes just now especially mentioned, there is a double apparatus which can hardly be treated of in conjunction with the sense organs, because its sensory functions have not been sufficiently made out, and which will therefore rather be considered along with the brain and central nervous system.
This apparatus is usually known under the name of the lateral organs.
As to the Mesonemertini, in the most primitive genus, Carinella, we do not find any lateral organs answering to the description above given.
The development of these organs, which in the Protonemertine are but grooves in the epidermis, not far removed from the similar cephalic slits of many Turbellaria, reaches its height in Drepanophorus.
The exit of these organs takes many shapes, of value in systematic work.
Whether in the Metanemertines, where the blood fluid is often provided with haemoglobiniferous disks, the chief functions of the side organs may not rather be a sensory one needs further investigation.
With respect to the sense organs of the Nemertines, we find that eyes are of rather constant occurrence, although many Heteronemertines living in the mud appear to be blind.
Besides these more highly differentiated organs of vision, more primitive eyes are present in others down to simple stellate pigment specks without any refracting apparatus.
Organs of hearing in the form of capsules containing otoliths have only been very rarely observed, apparently only in Metanemertini.
As a rule these organs only extend a short way along the anterior end of the body, a concentration which we may associate with the development of a vascular system I--- to bring the products of excretion to a fixed spot.
As to the development of the different organs, there is still much that remains doubtful.
The origin of the lateral organs has already been noticed; that of the nerve system is essentially epiblastic.
There are no specialized sense-organs or vascular or respiratory systems. There is a wide body-cavity, but as this has no connexion with the renal or reproductive organs it cannot be regarded as a coelom, but probably is a blood-space or haemocoel.
The tips of these tufts enclose a flamecell similar to those found in Platyhelminths, &c., and these probably function as excretory organs.
As the animals become adult, diverticula arise on the tubes of these organs, which develop either spermatozoa or ova.
The generative organs occupy a large part of the body cavity.
There are no alimentary canal or specialized organs for circulation or for respiration.
Kaiser has described as kidneys two organs something like minute shrubs situated dorsally to the generative ducts into which they open.
By this time the embryo has all the organs of the adult perfected save only the reproductive; these develop only when the first host is swallowed by the second or final host, in which case the parasite attaches itself to the wall of the alimentary canal and becomes adult.
Opulus, guelder rose, in the cultivated forms of which the corolla has become enlarged at the expense of the essential organs and the flowers are neuter.
They were intended to be the chief organs of internal administration, and have, in fact, discharged this function, especially under the First and Second Empire, surviving, though with diminished importance, under the other forms of government which modern France has seen.
Joly, the very young larvae have no breathing organs, and respiration is effected through the skin.
In 1865 Kowalevsky discovered that the organs of respiration consist of numerous pairs of gill-slits leading from the digestive canal through the thickness of the body-wall to the exterior.
It seems likely that the coelomic pore-canals were originally excretory organs, but in the existing Enteropneusta the pore-canals (especially the collar canals) have, as we have seen, acquired new functions or become vestigial, and the function of excretion is now mainly accomplished by a structure peculiar to the Enteropneusta called the glomerulus, a vascular complex placed on either side of the anterior portion of the stomochord, projecting into the proboscis-coelom.
Both dorsal and ventral branches supply the generative organs.
Sense organs are unknown in the adult.
The larval forms are provided with eye-spots, but no very specialized sense organs are found in the adult.
Their minute structure is closely similar in the two cases; the leaf-like plates receive blood from the great sternal sinus, and serve as respiratory organs.
Both belong to the category of " coelomoducts," namely, r- ' tubular or funnel-like portions of the coelom opening to the exterior in pairs in each somite (potentially,) and usually persisting in only a few somites as either "urocoels" (renal organs) or "gonocoels"(genital tubes).
It must be confessed that we are singularly ignorant as to the functional significance of these remarkable organs - the entosternites.
In Scorpio the completion of the horizontal plate by oblique flaps, so as to form an actual diaphragm shutting off the cavity of the prosoma from the rest of the body, possibly gives to the organs contained in the anterior chamber a physiological advantage in respect of the supply of arterial blood and its separation from the venous blood of the mesosoma.
Muscular fibres connected with the suctorial pharynx are in Limulus inserted into the entosternite, and the activity of the two organs may be correlated.
The blood is brought to the respiratory organs in both cases by a great venous collecting sinus having a ventral median position.
In any case it is clear that we have in these muscles an apparatus'for causing the blood to flow differentially in increased volume into either the pericardium, through the veins leading from the respiratory organs, or from the body generally into the great sinuses which bring the blood to the respiratory organs.
These muscles act so as to pump the blood through the respiratory organs.
It is not surprising that with so highly developed an arterial system Limulus and Scorpio should have a highly developed mechanism for determining the flow of blood to the respiratory organs.
The Eu-arachnida are divided into two grades with reference to the condition of the respiratory organs as adapted to aquatic or terrestrial life.
The mouth lying far back, so that the basal segments of all the prosomatic appendages, excepting those of the 1st pair, are capable of acting as masticatory organs.
The appendages of the mesosoma generally suppressed; in the more primitive forms one or two pairs may be retained as organs subservient to reproduction or silkspinning.
Scorpions do not possess spinning organs nor form either snares or nests, so far as is known.
Respiratory organs atrophied.
Remaining pairs of appendages with their basal segments immovably fixed to the sternal surface, similar in form, the posterior three pairs furnished with two claws supported on long stalks; the basal segments of the 6th pair bearing five pairs of tactile sensory organs or malleoli.
Respiratory organs tracheal, opening upon the ventral surface of the 2nd and 3rd, and sometimes also of the 4th somite of the opisthosoma.
Respiratory organs tracheal, opening by a pair of spiracles in the prosoma above the base of the fifth appendage on IV III I composed, at least in many cases, of eleven somites, the 1 1 th somite very small, often hidden within the loth.
Respiratory organs in the form of tracheal tubes opening by a pair of stigmata in the 2nd and 3rd somites of the opisthosoma.
Respiratory organs tracheal, opening by a pair of stigmata situated immediately behind the basal segments of the 6th pair of appendages on what is probably the sternum of the 2nd opisthosomatic somite and also in some cases upon the 5th segment of the legs.
The intromittent organs of the male are remarkable for their complexity and elaboration.
The town-hall, a large florid building of Classic order, stands on an eminence, and its clock tower forms a landmark; it contains the spacious Centennial Hall (commemorating the first Australian colonization here in 1787), and has one of the finest organs in the world.
The first English paper was the Natal Witness, started in 1845 and still one of the leading organs of public opinion.
The latter depend, it is true, on bodily organs during our earthly sojourn, but the dependence is not necessary.
For the diseases of the stomach in general see Digestive Organs; and for special forms Gastritis, Gastric Ulcer, Dyspepsia, &C.; also Abdomen (Abdominal Surgery).
The invasion of the lymphatic glands and the spreading of the growth into neighbouring organs, render the successful operative treatment of gastric cancer hazardous and disappointing.
Among the regular organs of the academy are the Transactions (from 1840), in some 60 vols., and the Annuals.
Of these one of the most notable is Cyril Horvath, whose treatises published in the organs of the academy display a rare freedom and comprehensiveness of imagination.
After 1872, in addition to its regular organs, it issued Hungarian translations of several popular scientific English works, as, for instance, Darwin's Origin of Species; Huxley's Lessons in Physiology; Lubbock's Prehistoric Times; Proctor's Other Worlds than Ours; Tyndall's Heat as a Mode of Motion, &c. Versions were also made of Cotta's Geologie der Gegenwart and Helmholtz's Populcire Vorlesungen.
On the eve of war the university and middle-school students had five or six newspaper organs of their own - notably Jugoslavija in.
But, as applied to lower and more obscure forms of life, teleology presented alfnost insurmountable difficulties; and consequently, in place of exact experiment and demonstration, the most reckless though ingenious assumptions were made as to the utility of the parts and organs of lower animals.
These infarcts are most common in organs provided with a terminal circulation, such as prevails in the kidney and spleen.
The terminal branches of the arteries supplying these organs are usually described as not anastomosing but many, if not all, of Cohnheim's end-arteries have minute collateral channels; which, however, are usually insufficient to completely compensate for the blocking that may occur in these arteries, therefore, when one of them is obstructed, the area irrigated by it dies from malnutrition.
Mere enlargement of an organ does not imply that it is in a state of hypertrophy, for some of the largest organs met with in morbid anatomy are in a condition of extreme atrophy.
Some organs are subject to enlargement from deposition within them of a foreign substance (amyloid, fat, &c.).
True hypertrophy is commonly found in the hollow muscular organs such as the heart, bladder and alimentary canal.
Or again, in the case of paired organs, if one be removed by operation, or destroyed by disease, the other at once undertakes to carry on the functions of both.
The loss of an eye will be followed by atrophy of the optic nerve; the tissues in a stump of an amputated limb show atrophic changes; a paralysed limb from long disuse shows much wasting; and one finds at great depths of the sea fishes and marine animals, which have almost completely lost the organs of sight, having been cut off for long ages from the stimuli (light) essential for these organs, and so brought into an atrophic condition from disuse.
The somatic cells represent communities or republics, as it were, which we name organs and tissues, but each cell possesses a certain autonomy and independence of action, and exhibits phenomena which are indicative of vitality.
Thus it is laid down in large quantity in cirrhosis of the liver, kidney or lung, and reacts upon these organs by contracting and inducing atrophy.
In diabetes mellitus, in which there is marked derangement in metabolism, extreme fatty changes are occasionally found in the organs, and the blood may be loaded with fat globules.
The coloured fats, or lipochromes, are found normally in some of the cells of the internal organs, and under certain pathological conditions.
But their disintegration is more commonly brought about by " phagocytosis " on the part of the phagocytic cells in the different organs concerned with the function of haemolysis, i.e.
Cellular activity and oxygen appear to be essential for its development; it is found usually in the cells of certain organs, or it may be deposited in the intercellular tissues.
Haemosiderin in the normal process of haemolysis is stored up in the cells of certain organs until required by the organism for the formation of fresh haemoglobin.
Amyloid develops in various organs and tissues and is commonly associated with chronic phthisis, tubercular disease of bone and joints, and syphilis (congenital and acquired).
The female organs of certain cryptogams, for instance, exert a positive chemiotactic action upon the spermatozoids, and probably, as Pfeffer suggests, the chemical agent which exerts the influence is malic acid.
There is no doubt that the organs were also examined by opening the bodies of living persons - criminals condemned to death being given over to the anatomists for this purpose.
Broussais's system, to which he gave the name of "Medecine physiologique," did much indirect good, in fixing attention upon morbid changes in the organs, and thus led to the rise of the strongly opposed anatomical and pathological school of Corvisart, Laennec and Bayle.
The result of his discovery was an entire revolution in the knowledge of diseases of the chest; but it would be a mistake to forget that an essential factor in this revolution was the simultaneous study of the condition of the diseased organs as seen after death.
The pathologico-anatomical method was also followed with great zeal and success by Gaspard Laurent Bayle (1774-1816), whose researches on tubercle, and the changes of the lungs and other organs in consumption, are the foundation of most that has been done since his time.
Thus the reciprocity of the various organs, maintained throughout the divisions of physiological labour, is not merely a mechanical stability; it is also a mutual equilibration in functions incessantly at work on chemical levels, and on those levels of still higher complexity which seem to rise as far beyond chemistry as chemistry beyond physics.
Now the cellular pathology of the blood, investigated by the aid of modern staining methods, is as important as that of the solid organs; no clinical investigator - indeed, apart from research, no practitioner at this day - can dispense with examination of the blood for purposes of diagnosis; its coagulability and the kinds and the variations of the cells it contains being evidence of many def i nitely morbid states of the body.
It is now fully recognized that diseases of infants and children, of the insane, of the generative organs of women, of the larynx, of the eye, have been brought successively into the light of modern knowledge by "specialists," and by them distributed to the profession; and that in no other way could this end have been attained.
In the middle part of the century, by a natural exaggeration of the importance of newly-discovered local changes in the pelvic organs, much harm was done to women by too narrow an attention to the site, characters and treatment of these; the meddlesomeness of the physician becoming in the temperament of woman.
The reproductive organs consist of the parts shown in fig.
A well-developed cellular parenchyma forms a matrix in which the muscular, excretory and generative organs are imbedded.
In one family (Ligulidae) the segmentation is only expressed in the metameric distribution of the generative organs and the worm is externally unisegmental.
In such cases the male organs are regarded as indicating the dorsal surface, the female organs as belonging to the ventral surface.
It bears adhesive organs that are either suckers or hooks, and may develop into the most varied outgrowths in order to give increased firmness of attachment to its host.
These complex organs have apparently arisen by the increase in depth and differentiation of an accessory sucker such as is borne on the phyllidia of the former group. Lastly, the scolex of the more familiar Taeniidae (Tetracotylea) carries a rostellum encircled with hooks and four cup-shaped suckers the margins of which do not project beyond the surface of the body.
In every species the segments develop from the scolex distally and increase in size with the maturation of the contained female genital organs.
In special cases, however, a proglottis may be detached before attaining full growth, and with its generative organs in an imperfectly developed condition.
The Cestodes of Elasmobranch fish offer more convincing examples of independent growth of the proglottides, for these are often set free with only the male organs developed, and each attains twice the size of the parental strobila.
The mass of the body consists of richly branched stellate cells - the mesenchyma - and imbedded in this plasmic tissue are the nervous, excretory, muscular and generative organs.
These organs may be raised on a short stalk, their cavity subdivided into loculi, and provided in some cases with hooks.
Each cansists of an eversible hollow tentacle provided with hooklets and capable of introversion within a mem The excretory organs consist of flame-cells, richly convoluted canaliculi, and a pair of longitudinal canals leading to the exterior by one or more pores.
The generative organs are of the complex hermaphroditic type described in Trematoda (q.v.).
It appears to be primarily related to the organs of attachment and to have attained greater elaboration than the rest of the nervous system because the proximal end is the most specialized and most stimulated portion of the worm.
The reproductive organs are usually repeated in each proglottis, and in some families two complete sets of such organs occur in each segment; in a few cases, parts only of the system are duplicated.
The structure of these organs is seen in figs.
Scolex with four outgrowths forming organs of adhesion and probably also of locomotion.
Whatever power they did secure, whether as potent subsidiary organs of the municipal polity for the regulation of trade, or as the chief or sole medium for the acquisition of citizenship, or as integral parts of the common council, was, generally speaking, the logical sequence of a gradual economic development, and not the outgrowth of a revolutionary movement by which oppressed craftsmen endeavoured to throw off the yoke of an arrogant patrician gild merchant.
In England the fraternities of journeymen, after struggling a while for complete independence, seem to have fallen under the supervision and control of the masters' gilds; in other words, they became subsidiary or affiliated organs of the older craft fraternities.
The chief peculiarities that distinguish Trematodes from their free-living allies, the Turbellaria, are the development of adhering organs for attachment to the tissues of the host; the replacement of the primitively ciliated epidermis by a thick cuticular layer and deeply sunk cells to ensure protection against the solvent action of the host; and (in one large order) a prolonged and peculiar life-history.
The only organs that exhibit any sign of degeneration are those of sense, but in the ectoparasitic Trematodes simple eye-like structures are present and perhaps serve as organs of temperature.
Speaking generally each species of parasite has a particular host, upon the blood of which it nourishes itself and matures its reproductive organs.
If ectoparasitic and attached to the skin, apertures or gills, the Trematode adopts more elaborate adhesive organs and undergoes a less complex development than are required for the endoparasitic members of the class.
The female organs consist of distinct ovaries and yolk-glands, the ducts of which uniti.
In these, the male organs ripen before the ova and spermatozoa may pass into the uterus before the external pore is formed (Looss).
The body contains in miniature all the organs of the adult fluke, including the gonads and in addition "eye-spots," a stylet, rod-cells and cystogenous cells.
The ciliated larva escapes from the egg into the water and enters an intermediate host (leech, mollusc, arthropod, batrachian or fish) where it undergoes a metamorphosis into a second stage in which most of the adult organs are present.
Among the other manufactories are flouring and grist mills, planing mills, foundries, and factories for making agricultural implements, United States mail boxes, furniture, pianos, organs, automobiles, toys and electrical supplies.
Reproductive organs with ducts leading to the vestibule.
The periodical histolysis may be partly due to the absence of specific excretory organs and to the accumulation of pigmented excretory substances in the wall of the alimentary canal.
The inner layer of the polypide-bud gives rise to the structures usually regarded as ectodermic and endodermic, the outer layer to the mesodermic organs.
Both kinds of reproductive organs may occur in a single zooecium, and the reproductive elements pass when ripe into the body-cavity.
This is followed by the atrophy of many of the larval organs, including the brain, the sense-organ and the ciliated ring.
In the Cyclostomata the primary embryo undergoes repeated fission without developing definite organs, and each of the numerous pieces so formed becomes a free larva, which possesses no alimentary canal.
Beet sugar is also largely manufactured, and the inhabitants of the Black Forest have long been celebrated for their dexterity in the manufacture of wooden ornaments and toys, musical boxes and organs.
These periodicals had now become extremely numerous, and many of the leading London publishers found it convenient to maintain their own particular organs.
A number of special organs came into existence about this period.
Nearly all departments of learning possessed their several special periodical organs about the close of the 17th or the beginning of the 18th century.
Other centres began to feel the need of similar organs of opinion.
No subject of human interest is now without one or indeed several organs.
Among the manufactures of Derby are pianos and organs, woollen goods, pins, keys, dress stays, combs, typewriters, corsets, hosiery, guns and ammunition, and foundry and machine-shop products.
Their organs of locomotion are the ribs, the number of which is very great, nearly corresponding to that of the vertebrae of the trunk.
The recovering patient suffers from haemorrhagic extravasations in various organs, besides from the lungs, nose, mouth and bowels.
It is true that there was no rivalry between the new organization and the old, as in Asia and Phrygia, for the Western Montanists recognized in its main features the Catholic organization as it had been developed in the contest with Gnosticism; but the demand that the "organs of the Spirit" should direct the whole discipline of the congregation contained implicitly a protest against the actual constitution of the Church.
The only sense organs described are eyes, which occur in some species, and may number one to four pairs.
The other attitude, however, is that into which simple-minded Latin peasants actually lapse, as it is also that which characterizes other religions ancient or modern which use pictures or sculptures of gods, demons, men, brutes, or of particular parts and organs of the same.
The general characters of the jaws have been mentioned above, and in detail there is great variation in these organs among the different families.
The organs and instincts for egg-laying and foodproviding are perhaps the most remarkable features in the economy of the Hymenoptera.
Among the manufactures are toys, furniture, overalls and organs, the Estey and the Carpenter organs being made there.
The piercing portions of the latter - representing their inner lobes or laciniaelie median to the mandibular piercers in the natural position of the organs.
Eleven abdominal segments can be recognized, at least in the early stages; as the adult condition is reached, the hinder segments become reduced or modified in connexion with the external reproductive organs, and show, in some male Hemiptera, a marked asymmetry.
The Hemiptera are remarkable for the variety of their stridulating organs.
They are of extremely widespread occurrence; there is hardly one of the chief classes of animals which does not furnish hosts for these parasites, scarcely one of the common tissues or organs of the Metazoan body which may not be liable to infection.
Castoreum is a substance contained in two pear-shaped pouches situated near the organs of reproduction, of a bitter taste and slightly foetid odour, at one time largely employed as a medicine, but now used only in perfumery.
No organs of circulation or respiration are known; but the nervous system is well developed, and consists of a pair of ganglia corresponding with the limbs and connected by longitudinal commissural chords.
The sexes are not distinct, the sexual organs being represented by a pair of testes and a single ovary, which open together into the posterior end of the alimentary canal.
These last characteristics also separate them essentially from the Pycnogonida, some members of which resemble them to a certain extent in having only four pairs of limbs, no gnathites, no respiratory organs, a ganglionated ventral nervous system, and the abdomen reduced to a mere rudiment projecting between the last pair of legs.
From references which can be gathered from patristic writings it is abundantly evident that the belief in the mystical meaning of marks on the "organ of organs" was a part of the popular philosophy of their times.
For, by representing the prosecution of its party-political objects as a championship of the Catholic Church, Ultramontanism seeks to acquire the support of the official organs of that Church, and the good will of all circles interested in her welfare; while at the same time it strives to discredit any attempt at opposition by branding it as an assault on the orthodox faith.
The volatile oils have for centuries been regarded as of value in disorders of the reproductive organs, and the reputation of myrrh in this connexion is simply a survival of this ancient but ill-founded belief.
The system of Linnaeus was founded on characters derived from the stamens and pistils, the so-called sexual organs of the flower, and hence it is often called the sexual system.
One of the early supporters of this natural method was Augustin Pyramus de Candolle (1778-1841), who in 1813 published his Theorie elementaire de la botanique, in which he showed that the affinities of plants are to be sought by the comparative study of the form and development of organs (morphology), not of their functions (physiology).
The idea of the existence of separate sexes in plants was entertained in early times, long before separate male and female organs had been demonstrated.
Theophrastus, who succeeded Aristotle in his school in the 114th Olympiad, frequently mentions the sexes of plants, but he does not appear to have determined the organs of reproduction.
Pliny, who flourished under Vespasian, speaks particularly of a male and female palm, but his statements were not founded on any real knowledge of the organs.
From Theophrastus down to Caesalpinus, who died at Rome in 1603, there does not appear to have been any attention paid to the reproductive organs of plants.
Camerarius, professor of botany and medicine at Tubingen, published a letter on the sexes of plants, in which he refers to the stamens and pistils as the organs of reproduction, and states the difficulties he had encountered in determining the organs of Cryptogamic plants.
Soon after the promulgation of Linnaeus's method of classification, the attention of botanists was directed to the study of Cryptogamic plants, and the valuable work of Johann Hedwig (1730-1799) on the reproductive organs of mosses made its appearance in 1782.
He was one of the first to point out the existence of certain cellular bodies in these plants which appeared to perform the functions of reproductive organs, and to them the names of antheridia and pistillidia were given.
He showed that the gaseous constituents of the air contribute largely to the nourishment of plants, and that the leaves are the organs which elaborate the food; the importance of leaves in nutrition had been previously pointed out by Malpighi in a short account of nutrition which forms an appendix to his anatomical work.
The phenomena of movements of the organs of plants attracted the attention of John Ray (1693), who ascribed the movements of the leaf of Mimosa and others to alteration in temperature.
The pure acid thus obtained is a most dangerous substance to handle, its vapour even when highly diluted with air having an exceedingly injurious action on the respiratory organs, whilst inhalation of the pure vapour is followed by death.
Whenever opinions did happen to be expressed which could be construed as criticism of Austria or Germany the offenders were speedily punished, and it was not long before the political leaders of the Czechs and Slovaks found themselves in confinement, some of them under sentence of death, while the Czech and Slovak press was subjected to a rigorous censorship and many of its organs prohibited from appearing.
To these three characters the Hydrozoa add a fourth which is distinctive of the subdivision of the Coelenterata termed the Cnidaria; that is to say, they always possess peculiar stinging organs known as nettle-cells, or nematocysts (Cnidae), each produced in a cell forming an integral part of the animal's tissues.
In this way is formed a ring of tentacles, the most characteristic organs of the Cnidaria.
The ectoderm retains its ciliation only in the sensory organs.
It teems with anachronisms; thus we have mention of the mass and organs, and also of a German servant.
The Times (semi-weekly 1817; daily 1841) was one of the most powerful Democratic organs in the period before the middle of the, 9th century, and had Gideon Wells for editor 1826-1836.
Flowers in which the relative position of the organs allows of spontaneous self-pollination may be all alike as regards length of style and stamens (homomorphy or homostyly), or differ in this respect (heteromorphy) the styles (From Strasburger's by permission of Gustav Fischer.) FIG.
In the latter respect, and in the fact that they frequently develop by a metamorphosis, they approach the Mollusca, but they differ from that group notably in the occurrence of metameric segmentation affecting many of the systems of organs.
In the male the first one or two pairs of feet are modified into grasping organs.
The limbs, including antennae and mouth organs, never exceed seven definite pairs.
The " brush-formed " organs of the Podocopa are medially placed, and, in spite of their sometimes forward situation, Miller believes among other possibilities that they and the penis in the Cypridinidae may be alike remnants of a third pair of legs, not homologous with the penis of other Ostracoda (Podocopa included).
In this tribe the males have both antennae of the first pair as sensory organs.
These are a chain of small bones belonging to the first four vertebrae, which are much modified, and connecting the air-bladder with the auditory organs.
Gymnotus is the only genus of - the family which possesses electric organs.
It was considered to be the work of inspired men, of men whom the Holy Spirit, at that time specially active in the Church, had chosen as its organs.
The English reviews were at that time practically publishers' organs, the articles in which were written by hackwriters instructed to praise or blame according to the publishers' interests.
The fundamental idea that Yahweh guides His people by the word of revelation is older than the separation of special classes of theocratic organs; Moses, indeed, is not only prophet and priest, but judge and ruler.
This appendage is merely a fold of the skin, ornamental and sexual; it has no cavity in its interior, and has no communication with the mouth or with the respiratory organs; it is supported by the posterior horns of the hyoid bone, and can be erected and spread at the will of the animal.
The mastication causes a copious flow of saliva of a brick-red colour, which dyes the mouth, lips and gums. The habit blackens the teeth, but it is asserted by those addicted to it that it strengthens the gums, sweetens the breath and stimulates the digestive organs.
In tracing the phylogeny, or ancestral history of organs, palaeontology affords the only absolute criterion on the successive evolution of organs in time as well as of (progressive) evolution in form.
Thus we observe persistent organs and persistent types of animals, analogous organs and analogous types of animals, and this analogy applies still further to the rival and more or less contradictory hypotheses of the sudden as distinguished from the gradual appearance of new parts or organs of animals, and the sudden appearance of new types of animals.
Origin from Primitive or Stem Forms. - As already observed, the same principles apply to groups of animals as to organs and groups of organs; an organ originates in a primitive and unspecialized stage, a group of animals originates in a primitive or stem form.
A very important evolutionary principle is that in such secondary returns to primary phases lost organs are never recovered, but new organs are acquired; hence the force of Dollo's dictum that evolution is irreversible from the point of view of structure, while frequently reversible, or recurrent, in point of view of the conditions of environment and adaptation.
Thus both invertebrate and vertebrate palaeontologists have reached independently the conclusion that the evolution of groups is not continuously at a uniform rate, but that there are, especially in the beginnings of new phyla or at the time of acquisition of new organs, sudden variations in the rate of evolution which have been termed variously " rhythmic," "pulsating," " efflorescent," "intermittent " and even " explosive " (Deperet).
The rapid variation of certain groups of animals or the acceleration of certain organs is also not evidence of the sudden appearance of new adaptive characters.
Internal causes of extinction are to be found in exaggeration of body size, in the hypertrophy or over-specialization of certain organs, in the irreversibility of evolution, and possibly, although this has not been demonstrated, in a progressive reduction of variability.
Among still other causes are great bulk, which proves fatal under certain new conditions; relatively slow breeding; extreme specialization and development of dominant organs, such as horns and tusks, on which for a time selection centres to the detriment of more useful characters.
The latter view is unfortunately confirmed by the undoubted fact that Caesar treated with scant respect the historical institutions of Rome, which with their magnificent traditions might still have been the organs of true political life.
The name medusa is suggested by the tentacles, usually long and often numerous, implanted on the edge of the umbrella and bear the stinging organs of which sea-bathers are often disagreeably aware.
When the prey comes into contact with the tentacles it is paralysed, and at the same time held firmly, by the barbed threads shot out from the stinging organs or nematocysts.
The gonads or generative organs may be produced either in the ectoderm or the endoderm.
A and B represent the same animal, some of the organs being shown in one figure and some in the other.
Other ciliated organs to be noticed are the proboscis cup of Bdelloidaceae, and the toes of Pedalion.
The sense organs are eyes, antennae, sensory styles and a statocyst in a few species.
They are possibly organs of external taste (smell) as well as of touch.
The male organs are usually a testis, a large seminal bladder and a protrusible penis.
The parasites are frequently more numerous in the spleen, bone-marrow, kidneys, &c., than elsewhere, and it has been found that multiplication goes on rather more actively in the capillaries of these organs.
Ingestion and dissolution of the Trypanosomes by phagocytes has frequently been observed; and it is probable also that the haematopoietic organs secrete some substance which exerts a harmful action on the parasites, and causes them to undergo involution and assume weird-looking " amoeboid " and " plasmodial " forms.
The tomb of William I., the founder's father - a magnificent porphyry sarcophagus contemporary with the church, under a marble pillared canopy - and the founder William II.'s tomb, erected in 1575, were both shattered by a fire, which in 1811 broke out in the choir, injuring some of the mosaics, and destroying all the fine walnut choir-fittings, the organs, and most of the choir roof.
This feature is the existence of a supreme instrument of government, a document, enacted by the people, which controls, and cannot be altered by, any or all of the ordinary organs of government.
But, taking the history of the republic as a whole, that equilibrium between the several organs of the government which the Constitution was intended to secure has been substantially maintained.
Nevertheless, her cleverness, volubility, energy and will-power enabled her to maintain her ground, and when she died on the 8th of May 1891 (White Lotus Day), at the theosophical headquarters in the Avenue Road, London, she was the acknowledged head of a community numbering not far short of 100,000, with journalistic organs in London, Paris, New York and Madras.
No accessory glands or copulatory organs are ever present in Lamellibranchs.
Let us now examine the organs which lie beneath the mantle-skirt of Anodonta, and are bathed by the current of water which circulates through it.
These organs are characteristic of all Lamellibranchs; they do not vary except in size, being sometimes drawn out to streamer-like dimensions.
The gill-plates have a structure very different from that of the labial tentacles, and one which in Anodonta is singularly complicated as compared with the condition presented by these organs in some other Lamellibranchs, and with what must have been their original condition in the ancestors of the whole series of living Lamellibranchia.
The blood makes its way by large veins to a venous sinus which lies in the middle line below the heart, having the paired renal organs (nephridia) placed between it and that organ.
The renal organs may be more ramified in other Lamellibranchs than they are in Anodonta.
The glands secrete hippuric acid which passes from the pericardium into the renal organs.
The organs are developed as invaginations of the epidermis of the foot, and in the majority of the Protobranchia the orifice of invagination remains open throughout life; this is also the case in Mytilus including the common mussel.
It remains in this condition for a period of two to six weeks, and during this time the permanent organs are developed from the cells of two symmetrical cavities behind the adductor muscle.
The glochidium is formed by the precocious development of the anterior adductor and the retardation of all the other organs except the shell.
When the larval development is completed the test is cast off, its cells breaking apart and falling to pieces leaving the young animal with a well-developed shell exposed and the internal organs in an advanced state.
The four orders now retained exhibit successive stages in the modification of the ctenidia by reflection and concrescence of the filament, but other organs, such as the heart, adductors, renal organs, may not show corresponding stages.
On the contrary considerable differences in these organs may occur within any single order.
Sensation is not the reception of the selfsame essence of an external body, but one's perception of one's sentient organism as affected, and especially of its organs resisting one another, e.g.
The reproductive organs, both ovaries and testes, become fused together in the middle of the body.
There are only six or eight Malpighian tubes - contrasting with the large number of these excretory organs found in the Orthoptera and Plecoptera.
The vagina is a dilatable muscular passage, lined with mucous membrane, which leads from the uterus to the external generative organs; its direction is, from the uterus, downward and forward, and its anterior and posterior walls are in contact, so that in a horizontal section it appears as a transverse slit.
The vulva or pudendum comprises all the female external generative organs, and consists of the mons Veneris, labia majora and minora, clitoris, urethral orifice, hymen, bulbs of the vestibule, and glands of Bartholin.
From the above description it will be seen that all the parts of the male external genital organs are represented in the female, though usually in a less developed condition, and that, owing to the orifice of the vagina, they retain their original bi-lateral form.
The development of the reproductive organs is so closely interwoven with that of the urinary that some reference from this article to that on the Urinary System is necessary.
This indicates that the custom of taking out these organs and wrapping them separately was already in vogue in the most lavish form of burial.
The Christians of the early centuries, looking for corporeal resurrection, avoided the incisions, extraction of organs, &c., practised by their pagan forefathers, and buried the body entire after pickling it in salt.
Such organs are absent in Mollusca in the adult state, but a pair of nephridia usually occurs in the larva.
In Mollusca the coelom is reduced and consists of two parts, the pericardial cavity which surrounds the heart, and the cavity of the gonads or generative organs.
There is usually one pair of coelomic ducts leading from the pericardium to the exterior, and these are the excretory organs or kidneys, formerly known as the organs of Bojanus.
The Dibranchia, with only one pair of branchiae, one pair of renal organs, and one pair of genital ducts, are much more recent, not appearing till the end of the Secondary epoch, and therefore must be regarded as descended from the Tetrabranchia.
The characteristic organs of Mollusca are the mantle and shell, the foot, the ctenidia and the radula, of which all but the last are external.
The last is between the pericardium and the foot; from it the blood passes through the renal organs to the ctenidia.
In some cases the coelom is formed as a single cavity, and renal and generative organs are formed from its walls.
This is the primitive method, but in other cases the organs mentioned may be formed separately in the mesoderm.
The renal organs are tubular outgrowths of the pericardial parts of the coelom; the reproductive cells are derived from cells lining the generative portion.
In the larvae of several Gastropoda and Lamellibranchia occur excretory organs which have the characters of true nephridia.
There is a single pair of these organs situated immediately behind the velum.
They invariably disappear before the adult stage is reached, but their presence in the larva is evidence that the ancestral mollusc possessed a pair of true nephridia quite distinct from the coelomic excretory organs, which are so characteristic of existing forms in the adult condition.
The ctenidia, it will be observed, have not yet been mentioned, and they are indeed the last of the characteristic Molluscan organs to make their appearance.
The Cephalopoda can be derived without much difficulty from the schematic Mollusc, if we assume that some metameric repetition of organs has occurred, as explained above in reference to the coelom.
Malarial fevers are also common, and diseases of the digestive organs, in great part easily preventible, figure among the principal causes of death.
One end of the body, through contact, during locomotion, with fresh tracts of medium and other forms of stimuli, has become more specialized than the rest, and here the nervous system and sense-organs are more densely aggregated than elsewhere, forming a means of controlling locomotion and of correlating the activities of the inner organs with the varying stimuli that impinge upon the body.
These protonephridia are the excretory organs.
The Platyelmia are hermaphrodite and the reproductive organs are complex.
The male organs consist of paired testes communicating by delicate canals with a protrusible penis.
The female organs are no less complex.
The study of Rhabdocoels (7) has led to the important discovery that the rudiment of the gonads and that of the pharynx are the first organs to appear, and that the alimentary sac arises independently of them.
He holds indeed that, in accordance with the law of substance, consciousness must be evolved from unconsciousness with the development of sense organs and a central nervous organ.
By thus supposing a psychical basis to evolution, Fechner, anticipating Wundt, substituted a psychical development of organs for Darwinian accidental variation.
I cannot separate touching from my tactile organs, seeing from my eyes, or hearing from my ears.
Next, finding that He gives signs of bodily works, but no signs of bodily organs, we can infer that God is a Spirit.
There are no specialized circulatory, respiratory or excretory organs.
An interesting feature of the development of Chaetognaths is that, as in some insects, the cells destined to form the reproductive organs are differentiated at a very early period, being apparent even in the gastrula stage.
The organs manufactured at Jagerndorf enjoy a good reputation.
In this constitution he declared that the competency of these various organs was not always clear, and that their functions were badly arranged; that certain of them had only a small amount of business to deal with, while others were overworked; that strictly judicial affairs, with which the Congregations had not to deal originally, had developed to an excessive extent, while the tribunals, the Rota and the Signatura, had nothing to do.
In a complete albino not only is all pigment absent in the skin, but also that which is normally present in deeper organs, such as the sympathetic nervous system and in the substantia nigra of the brain.
Trochilium apiforme, crabroniforme - present to bees and wasps is effected in the main by the loss of the scales from the wings, leaving these organs transparent.
The reproductive organs of the lichen are of a typically fungal character, i.e.
Zukal has suggested that they may play the part of water-absorbing organs.
The female sexual organs, the ?, ascogonia, would thus in the majority of cases develop by the aid of some reduced sexual process or the ascocarps be developed without relation to sexual organs.
Theoretically the lichens may be classified on the basis of their algal constituent, on the basis of their fungal constituent, or they may be classified as if they were homogeneous organisms. The first of these systems is impracticable owing to the absence of algal reproductive organs and the similarity of the algal cells (gonidia) in a large number of different forms. The second system is the most obvious one, since the fungus is the dominant partner and produces reproductive organs.
In actual practice the difference between the second and third methods is not very great since the fungus is the producer of the reproductive organs and generally the main constituent.
Most systems agree in deriving the major divisions from the characters of the reproductive organs (perithecia, apothecia, or basidiospore bearing fructification), while the characters of the algal cells and those of the thallus generally are used for the minor divisions.
Accordingly the general resurrection and the last judgment may be regarded as the temporal and local forms of thought to express the universal permanent truths that life survives death in the completeness of its necessary organs and essential functions, and that the character of that continued life is determined by personal choice of submission or antagonism to God's purpose of grace in Christ, the perfect realization of which is the Christian's hope for himself, mankind and the world.
Owen's description showed this view to be groundless, and he attributed the extraordinary development of the toucan's beak to the need of compensating, by the additional power of mastication thus given, for the absence of any of the grinding structures that are so characteristic of the intestinal tract of vegetable-eating birds - its digestive organs possessing a general simplicity of formation.
By growth is here meant mere increase in bulk, and by development the series of gradual modifications by which a plant, originally simple in its structure and conformation, becomes eventually complicated, and endowed with distinct parts or organs.
The reproduction of the higher plants takes place either asexually by the formation of buds or organs answering thereto, or sexually by the production of an embryo plant within the seed.
Bottom-Heat.----The " optimum " temperature, or that best suited to promote the general activity of roots, and indeed of all vegetable organs, necessarily varies very much with the nature of the plant, and the circumstances in which it is placed, and is ascertained by practical experience.
Moreover, although the green portions of the flower do indeed perform the same office as the leaves, the more highly coloured and more specialized portions, which are further removed from the typical leaf-form, do not carry on those processes for which the presence of chlorophyll is essential; and the floral organs may, therefore, in a rough sense, be said to be parasitic upon the green parts.
A check or arrest of growth in the vegetative organs seems to be a necessary preliminary to the development of the flower.
The largest pair of branchiae is placed immediately behind the renal openings and corresponds to the single pair of other molluscs, the organs being repeated anteriorly only (Metamacrobranchs) or anteriorly and posteriorly (Mesomacrobranchs).
The excretory organs are coelomoducts with an internal ciliated opening into the pericardium and an opening to the exterior.
The sense organs of the shell-valves have already been described.
The coelom differs from that of the Chitons in the fact that the cavities of the genital organs are continuous with it, and in the fact that there is only one pair of coelomoducts resembling the renal organs of Chitons, but serving also as genital ducts.
With regard to sense organs the epithelial papillae of the mantle have been mentioned.
There are no accessory generative organs.
But it is a widely recognized principle of morphology that a much modified animal is by no means modified to the same degree in all its organs.
A form which is primitive on the whole may show a more advanced stage of evolution in some particular system of organs than another animal which is on the whole more highly developed and specialized.
The chief industries are flax-spinning, rope-making, sugar refining, book printing, wool combing and dyeing, and it also manufactures beer, tobacco and cigars, cotton and woollen stuffs, furniture, organs and pianos; besides which there are saw, oil and grain mills, machine works, and numerous goldsmiths and silversmiths.
The functions of mycelial strands, rhizomorphs and sclerotia are not only to collect and store materials, but also to extend the fungus, and in many cases similar strands act as organs of attack.
As with other plants, so in fungi the essential process of fertilization consists in the fusion of two nuclei, but owing to the absence of well-marked sexual organs from many fungi, a peculiar interest attaches to certain nuclear fusions in the vegetative cells or in young spores of many forms. Thus in Ustilagineae the chlamydospores, and in Uredineae the teleutospores, each contain two nuclei when young, which fuse as the spores mature.
Klebs has shown that the development of zoosporangia or of oogonia and pollinodia respectively in Saprolegnia is dependent on the external conditions; so long as a continued stream of suitable food-material is ensured the mycelium grows on without forming reproductive organs, but directly the supplies of nitrogenous and carbonaceous food fall below a certain degree of concentration sporangia are developed.
They are characterized especially by the zygospores, but the asexual organs (sporangia) exhibit interesting series of changes, beginning with the typical sporangium of Mucor containing numerous endospores, passing to cases where, as in Thamnidium, these are accompanied with more numerous small sporangia (sporangioles) containing few spores, and thence to Chaetocladium and Piptocephalis, where the sporangioles form but one spore and fall and germinate as a whole; that is to say, the monosporous sporangium has become a conidium, and Brefeld regarded these and similar series of changes as explaining the relation of ascus to conidium in higher fungi.
In some forms we find definite male and female sexual organs (Sphaerotheca, Pyronema, &c.), in others the antheridium is abortive or absent, but the ascogonium (oogonium) is still present and the female nuclei fuse in pairs (Lachnea stercorea, Humaria granulata, Ascobolus furfuraceus); while in other forms ascogonium and antheridium are both absent and fusion occurs between vegetative nuclei (Humaria rutilans, and probably the majority of other forms).
Functional male and female organs have been shown to exist in Pyronema and Boudiera; in Lachnea stercorea both ascogonia and antheridia a are present, but the antheridium a1 is non-functional, the ascogonial _s- - (fema l e) nuclei fusing in pairs; /'y' this is also the case' in Humaria /;' h; granulate and Ascobolus furfurs -./ '"aceus, where the antheridium is _ / /, - entirely absent.
Besides the special ascocarps, accessory reproductive organs are known in the majority of cases in the form of conidia.
The receptacle ends above in appendages, each consisting of one or a few cells, some of which are the male organs, others the female organs, and others again may be barren hairs.
All the forms have the same life-history as the lepto forms of that group, so that there is no longer any trace of sexual organs.
Although the Uredineae clearly lead on to the Basidiomycetes, yet owing to their retaining in many cases definite traces of sexual organs they are clearly a more primitive group. Their marked parasitic habit also separates them off, so that they are best included with the Basidiomycetes in a larger cohort which may be called Basidiales.
Such obligate parasites may be epiphytic (Erysipheae), the mycelium remaining on the outside and at most merely sending haustoria into the epidermal cells, or endophytic (Uredineae, Ustilagineae, &c.), when the mycelium is entirely inside the organs of the host.
The latter fact, as well as the extraordinary fastidiousness, so to speak, of parasites in their choice of hosts or of organs for attack, point to reactions on the part of the host-plant, as well as capacities on that of the parasite, which may be partly explained in the light of what we 'now know regarding enzymes and chemotropism.
Some parasites attack many hosts and almost any tissue or organ (Botrytis cinerea), others are restricted to one family (Cystopus candidus) or genus (Phytophthora infestans) or even species (Pucciniastrum Padi), and it is customary to speak of rootparasites, leaf-parasites, &c., in expression of the fact that a given parasite occurs only on such organs - e.g.
In many Roman Catholic countries - in Spain, for example - it is usual for the faithful to spend much time in the churches in meditation on the "seven last words" of the Saviour; no carriages are driven through the streets; the bells and organs are silent; and in every possible way it is sought to deepen the impression of a profound and universal grief.
Great care should be taken in using dimethyl and diethyl sulphates, as the respiratory organs are affected by the vapours, leading to severe attacks of pneumonia.
Erie is the commercial centre of a large and rich grape-growing and agricultural district, has an extensive trade with the lake ports and by rail (chiefly in coal, iron ore, lumber and grain), and is an important manufacturing centre, among its products being iron, engines, boilers, brass castings, stoves, car heaters, flour, malt liquors, lumber, planing mill products, cooperage products, paper and wood pulp, cigars and other tobacco goods, gas meters, rubber goods, pipe organs, pianos and chemicals.
A post mortem examination was held, which showed not only grave derangement in the stomach and other organs, but a serious lesion of the brain.
The higher organs of local government, so far as these are representative, are based on the principle of a group or union of communes (Gemeindeverband).
There are, further, Verwaltungsgerichte (administrative courts) for the adjustment of disputes between the various organs of local government, and other special courts, such as military, consular and arbitration courts (Schiedsgericht).
The wife and children have also their domicile in the place where the husband or father has his.i Relief of the poor is one of the chief duties of the organs of local self-government.
Histriodrilus resembles Saccocirrus in the possession of two posterior adhesive processes, and to some extent in the structure of the complex genital organs, which, however, are restricted to a single segment.
But the way in which they usually diverge just over and in front of the eye has suggested the more probable idea, that they serve to guard these organs from thorns and spines while hunting for fallen fruits among the tangled thickets of rattans and other spiny plants.
On the inner surface is a layer of peritoneal epithelium, which is frequently ciliated, and at the bases of the retractor muscles is heaped up and modified into the reproductive organs.
All along one side is a microscopic ciliated groove, into which the mud does not seem to enter, and along which a continuous stream of water may be kept up. Possibly this is respiratory - there are no special respiratory organs.
The excretory organs are typical nephridia, with an internal ciliated opening into the body-cavity, and an external pore.
The organs are typically two, though one is often absent, e.g.
The cities appear equally Hellenic in their political organs and functions with boule and demos and popularly elected magistrates.
This shows us the normal organs of a Greek city, boule, ecclesia, prytaneis, &c., in full working, with the annual election of magistrates, and ordinary forms of public action.
And although it took several generations of poets to beat their music out to the perfection of the Virgilian cadences, yet in the rude adaptation of Ennius the secret of what ultimately became one of the grandest organs of literary expression was first discovered and revealed.
This, when garlic has been eaten, is evolved by the excretory organs, the activity of which it promotes.
Upper Egypt is healthier than Lower Egypt, where, especially near the coast, malarial fevers and diseases of the respiratory organs are not uncommon.
Side by side with these literary organs there exists a vernacular press largely devoted to nationalist propaganda.
The receptive organs of the muscular sense and of the semicircular canals are to be regarded as the sites of origin of this reflex tonus of the skeletal muscles.
From these, as in the eye, ear, and other sense organs, tonus is constantly initiated.
The tactual organs of the soles, and the muscular sense organs of limbs and trunk, are originating perceptions that indicate that the self is standing on the solid earth, yet the eyes are at the same time originating perceptions that indicate that the solid earth is far away below the standing self.
With certain of these it stands associated most closely, namely, with the vestibular, representing the sense organs which furnish data for appreciation of positions and movements of the head, and with the channels, conveying centripetal impressions from the apparatus of skeletal movement.
Certain it is that in the course of the waking day a great number of stimuli play on the sense organs, and through these produce disintegration of the living molecules of the central nervous system.
Could we assume that there is in the adult man reflex machinery which is of higher order than the merely spinal, which employs much more complex motor mechanisms than they, and is connected with a much wider range of sense organs; and could we assume that this reflex machinery, although usually associated in its action with memorial and volitional processes, may in certain circumstances be sundered from these latter and unattendant on them - may in fact continue in work when the higher processes are at a standstill - then we might imagine a condition resembling that of the somnambulistic and cataleptic states of hypnotism.
There is much uncertainty as to the influence of atropine on the secretions of the stomach, intestines, liver, pancreas and kidneys, and it is not possible to make any definite statement, save that in all probability the activities of the nerves innervating the glandcells in these organs are reduced, though they are certainly not arrested, as in the other cases.
The motor nerves of the arteries, of the bladder and rectal sphincters, and also of the bronchi, are paralysed by atropine, but the nervous arrangements of those organs are highly complex and until they are further unravelled by physiologists, pharmacology will be unable to give much information which might be of great value in the employment of atropine.
Usually, however, other leaves are present which are only indirectly concerned with the reproductive process, acting as protective organs for the sporophylls or forming an attractive envelope.
The seven series of Monocotyledons represent a sequence beginning with the most complicated epigynous orders, such as Orchideae and Scitamineae, and passing through the petaloid hypogynous orders (series Coronarieae) of which Liliaceae is the representative to Juncaceae and the palms (series Calycinae) where the perianth Ioses its petaloid character and thence to the Aroids, screw-pines and albuminous Dicotyledons the cotyledons act as the absorbents of the reserve-food of the seed and are commonly brought above ground (epigeal), either withdrawn from the seed-coat or carrying it upon them, and then they serve as the first green organs of the plant.
Their life-cycle, however, the structure of the reproductive organs and their whole organization proclaim them to be Bryophyta.
The reproduction of Characeae is characterized by a pronounced oogamy, the reproductive organs being the most highly differentiated among Chlorophyceae.
The sexual organs - oogonia and antheridia - are borne on special portions of the thallus in cavities known as conceptacles.
Both organs may occur in one conceptacle, as in Pelvetia, or each may be confined to one conceptacle or even one plant, as in Fucus vesiculosus.
The asexual organs in the case of Cutleria multifida arise on a crustaceous form, Aglaozonia reptans, formerly considered to be a distinct species.
The possession of two kinds of reproductive organs, unilocular and plurilocular sporangia, is general among the rest of the Phaeosporeae.
Bornet, however, called attention in 1871 to the fact that two kinds of plurilocular sporangia occurred in certain species of the genus Ectocarpus - somewhat transparent organs of an orange tint producing small zoospores, and also more opaque organs of a darker colour producing relatively larger zoospores.
Some Red Algae find a home in the gelatinous substance of Flustra, Alcyonidium and other polyzoa, only emerging for the formation of the reproductive organs.
Upon them also the reproductive organs arise in this family.
Melobesia callithamnioides gives rise to multicellular propagula; Griffithsia corallina is said to give rise to new individuals, by detaching portions of the thallus from the base of which new attachment organs have already arisen.
Turn ing first to the Rhodophyceae, both on account of the high place which they occupy among algae and also the remarkable uniformity in their reproductive processes, it is clear that, as is the case among Archegoniatae, the product of the sexual act never germinates directly into a plant which gives rise to the sexual organs.
The true Chantransia, however, bears its own sexual organs as well as monospores.
From the analogy of the higher plants observers have justly argued that when they have seen and marked the characters of the reproductive organs they have found the plant at the stage when it exhibits its most noteworthy features, and they have named and classified the species in accordance with these observations.
He believed that life was an expanding, growing force, and that animals responded to the environment by developing new wants, seeking to satisfy these by new movements and thus by their own striving producing new organs which were transmitted to their descendants.
And similarly in the development of a complicated organism, the suppression or doubling of a single cell or group of cells may bring about striking differences in the symmetry of the adult, or the reduction or increase in the number of metameric organs.
It is well known that some races and some organs in plants and animals are extremely variable, and that others are much less variable, and further, that whilst some of these differences may be due to intrinsic causes, others can be modified by experiment.
Every organism is an individual, its different parts, organs and functions being associated in a degree of intimacy that varies, but that corresponds roughly with the integration of the individual and its place in the ascending scales of animal or vegetable life.