A natural classification of the Hydroidea has yet to be put forward.
That Garrod has so very much advanced the classification of birds is ultimately due to his comprehensive anatomical knowledge and general insight.
It would be impracticable to go fully into the varieties of each specific form; but, partly as an example of modern geographical classification, partly because of the exceptional import of ance of mountains amongst the features of the land, one exception may be made.
Blanchard, " Recherches sur les caracteres osteologiques des oiseaux appliques a la classification," Ann.
Whilst the type of syrinx affords no help in classification, it is very different with its muscles.
A statement may now be given of Gadow's classification of birds, in which the extinct forms have been intercalated so far as possible.
It is certain, however, that no such classification can be considered final at present, but must undergo continual revision in the future.
The terms employed, especially for the subdivisions, cannot be easily translated into other languages, and the English equivalents in the following table are only put forward tentatively Richthofen'S Classification Of Mountains I.
The classification given here is for the most part that of Delage and Herouard.
Huxley, " On the Classification of Birds and on the Taxonomic Value of the Modifications of certain of the Cranial Bones..."
This way of using the characters of the syrinx for the classification of the Passeriformes seems simple, but it took a long time to accomplish.
As in the Gymnoblastea, the difficulty of uniting the hydroid and medusan systems into one scheme of classification is very great in the present state of our knowledge.
Latin and its nearest congeners, like Faliscan); and (d) Umbrian (or, as it may more safely be called, Iguvine), two principles of classification offer themselves, of which the first is purely linguistic, the second linguistic and topographical.
While the forms of the sea-bed are not yet sufficiently well known to admit of exact classification, they are recognized to be as a rule distinct from the forms of the land, and the importance Submarine of using a distinctive terminology is felt.
The fundamental form-elements may be reduced to the six proposed by Professor Penck as the basis of his double system of classification by form and origin.'
When a district like England is divided into edaphic areas, a general classification such as the following may be obtained:
The varieties of coast-lines were reduced to an exact classification by Richthofen, who grouped them according to the height and slope of the land into cliff-coasts (Steilkiisten)- narrow beach coasts with cliffs, wide beach coasts with cliffs, and 1 Rumpf, in German, the language in which this distinction was first made.
When the nature and effect of ecological factors have become more fully understood, it will be possible to dispense with the above artificial classification of factors, and to frame one depending on the action of the various factors; but such a classification is not possible in the present state of knowledge.
The classification of the land surface into areas inhabited by distinctive groups of plants has been attempted by many phytogeographers, but without resulting in any scheme of general acceptance.
The two kinds of persons present in the typical Hydroidea make the classification of the group extremely difficult, for reasons explained above.
From the point of view of the economy of the globe this classification by species is perhaps less important than that by mode of life and physiological character in accordance with environment.
ti Recently, Warmingi (1909: 136), assisted by VahI, has, odified his earlier classification, and adopted the following: fl A.
It is probable that further research will amend this classification in detail, but its main lines are generally accepted.
The following is the main outline of the classification that is adopted in the present article.
We may often distinguish between primary symptoms and secondary or subordinate symptoms, but for the purposes of classification in an article of this scope we shall only attempt to group the various cases under the more obvious signs of disease exhibited.
Such a system of classification, although convenient, is not the most natural one, and a sketch of the system which better expresses the relationships between the various subdivisions is given here.
A subject so vast and so incapable of classification cannot be discussed here, but its aesthetic principles may be illustrated by the extreme case of the trumpets and horns, which in classical times had no scale except that of the natural harmonic series.
It is a plain, straightforward description of the globe, and of the various phenomena of the surface, dealing only with definitely ascertained facts in the natural order of their relationships, but avoiding any systematic classification or even definitions of terms.
CLAssIFICATIoN o~ PLANTS
the Code ") has, however, made a more systematic study possible than could have resulted from the classification and interpretation of the other material.
If our knowledge of the life-histories of these organisms were perfect, their polymorphism would present no difficulties to classification; but unfortunately this is far from being the case.
The few characters assigned to the various groups are sufficiently diagnostic when taken together, although they are not always those upon which the classification has been established: - Class Aves I.
The resulting " classification is based on the examination, mostly autoptic, of a far greater number of characters than any that had preceded it; moreover, they were chosen in a different way, discernment being exercised in sifting and weighing them, so as to determine, so far as possible, the relative value of each, according as that value may vary in different groups, and not to produce a mere mechanical ` key ' after the fashion become of late years so common " (Newton's Dictionary of Birds, Introduction, p. 103).
But at present the word "leech" is applied to every member of the group Hirudinea, for the general structure and classification of which see Chaetopoda.
Gunther, " On the Structure and Affinities of Mnestra parasites Krohn; with a revision of the Classification of the Cladonemidae," Mitt.
Some account of the history of plant classification and the development of a natural system in which an attempt is made to show the actual relationships of plants, is given in the article BOTANY.
The above classification by Warming, although it was without doubt the best ecological classification which had, at the time, been put forward, has not escaped criticism.
The evidence against this view may be classed under two heads: first, comparative evidence; hydroids very different in their structural characters and widely separate in the systematic classification of these organisms may produce medusae very similar, at least so far as the essential features of medusan organization are concerned; on the other hydroids closely allied, perhaps almost indistinguishable, may produce gonophores in the one case, medusae in the other; for example, Hydractinia (gonophores) and Podocoryne (medusae), Tubularia (gonophores) and Ectopleura (medusae), Coryne (gonophores) and Syncoryne (medusae),-and so on.
The following tables, showing the growth of the largest towns in France, are drawn up on the basis of the fourth classification, which is used throughout this work in the articles on French towns, except where otherwise stated.
The vice of the book is excessive classification of bodily faculties, and over-subtlety in the discrimination of diseases.
Hence both polyp and medusa present characters for classification, and a given species, genus or other taxonomic category may be defined by polyp-characters or medusa-characters or by both combined.
The classification into epithelial organs, connective tissues, and the more specialized muscle and nerve, was largely due to him; and he proved the presence of neuroglia in the brain and spinal cord, discovered crystalline haematoidine, and made out the structure of the umbilical cord.
The geographers who have hitherto given most attention to the forms of the land have been trained as geologists, and consequently there is a general tendency to make origin or structure the basis of classification rather than form alone.
Within this classification of uniforms, there are several distinctions.
because of differences in classification.
Besides the system of charges thus prescribed in the classification and rate-sheet, each tariff provides for a certain number of special rates or charges made for particular lines of trade in certain localities, independently of their relation to the general system.
A classification may also be made, according to the work for which engines are designed, into passenger engines, goods engines, and shunting or switching engines.
Their shape and size varies greatly and is often of use in classification.
and these descriptions being almost without exception so drawn up as to be comparative are accordingly of great utility to the student of classification, though they have been so greatly neglected.
We have already seen that De Blainville, though fully persuaded of the great value of sternal features as a method of classification, had been compelled to fall back upon the old pedal characters so often employed before; but now the scholar had learnt to excel his teacher, and not only to form an at least provisional arrangement of the various members of the Class, based on sternal characters, but to describe these characters at some length, and so give a reason for the faith that was in him.
More importance is to be attached to his Nosology or Classification of Diseases.
The like must be said even of the contribution to the problem made by August Pott,' though he has helped to define one condition of success - the classification of the strata in " Western " texts - and has taken some steps in the right direction, in connexion with the complex phenomena of one witness, the Harklean Syriac.
The families are those which are enumerated in Garow's classification.
COLEOPTERA, a term used in zoological classification for the true beetles which form one of the best-marked and most natural of the orders into which the class Hexapoda (or Insecta) has been divided.
The number of described species can now hardly be less than 10o,000, but there is little agreement as to the main principles of a natural classification.
His contributions on the Mesozoic reptiles of Great Britain culminated in his complete rearrangement and classification of this group, one of his greatest services to palaeontology.
Horn (Classification of Coleoptera of N.
This classification is based partly upon special conditions of service, which make some articles more economical to carry than others (with particular reference to the question whether the goods are offered to the companies in car-loads or in small parcels), but chiefly with regard to the commercial value of the article, and its consequent ability to bear a high charge or a low one.
As a general classification the commissioners have divided the schemes that have come before them into three classes: (A) those which like ordinary railways take their own line across country; (B) those in connexion with which it is proposed to use the public roads conjointly with the ordinary road traffic; and (Neutral) which includes inclined railways worked with a rope, and lines which possess the conditions of A and B in about equal porportions.
of 0 70 m.; but as there is no example of type V., the classification is practically one of 1 '445 m.
DIPTERA (Sis, double, 7rTEpa, wings), a term (first employed in its modern sense by Linnaeus, Fauna Suecica, 1st ed., 1746, p. 306) used in zoological classification for one of the Orders into which the Hexapoda, or Insecta, are divided.
The wings, which are not capable of being folded, are usually transparent, but occasionally pigmented and adorned with coloured spots, blotches or bands; the wing-membrane, though sometimes clothed with minute hairs, seldom bears scales; the wing-veins, which are of great importance in the classification of Diptera, are usually few in number and chiefly longitudinal, there being a marked paucity of cross-veins.
The antennae of Diptera, which are also extremely important in classification, are thread-like in the more primitive families, such as the Tipulidae (daddy-long-legs), where they consist of a considerable number of joints, all of which except the first two, and sometimes also the last two, are similar in shape; in the more specialized families, such as the Tabanidae (horse-flies), Syrphidae (hover-flies) or Muscidae (house-flies, blue-bottles and their allies), the number of antennal joints is greatly reduced by coalescence, so that the antennae appear to consist of only three joints.
Bristles are usually present on the legs, and in the case of many families on the body also; those on the head and thorax are of great importance in classification.
His classification was founded mainly on the nature of the wings, and five of his orders - the Hymenoptera (bees, ants, wasps, &c.), Coleoptera (beetles), Diptera (two-winged flies), Lepidoptera (moths and butterflies), and Hemiptera (bugs, cicads, &c.) - are recognized to-day with nearly the same limits as he laid down.
The great advance in modern zoology as regards the classification of the Hexapoda lies in the treatment of a heterogeneous assembly which formed Linnaeus's order Neuroptera.
Diptera are divided into some sixty families, the exact classification of which has not yet been finally settled.
Before leaving the subject of classification it may be noted in passing that in 1906 Professor Lameere, of Brussels, proposed a :scheme for the classification of Diptera which as regards both the limits of the families and their grouping into higher categories, differs considerably from that in current use.
This classification has been very generally received, and most later schemes have been modifications of it.
viii., 1896) have written on the classification of the Formicidae.
Considerable progress has been made in the classification of the various races which occupy the continent to the west of the great Mongolian region.
It is evident that no permanent classification is possible of what is or is not of economic significance.
Again, the classification of an economic bibliography at once shows how varied has been the character of economic investigation, ranging from the most abstract speculation on the one hand to almost technical studies of particular trades on the other.
The former classification into Holochlamyda, Pneumochlamyda and Siphonochlamyda has been abandoned, as it was founded on adaptive characters not always indicative of true affinities.
As an extreme contrast to this After Westwood, c am odeif orm type, we take the maggot Modern Classification.
Classification Number of Species.
Nevertheless, the constant increase of our knowledge of insect forms renders classification increasingly difficult, for gaps in the series become filled, and while the number of genera and families increases, the distinctions between these groups become dependent on characters that must seem trivial to the naturalist who is not a specialist.
Brauer in his arrangement of these orders laid special stress on the nature of the metamorphosis, and was the first to draw attention to the number of Malpighian tubes as of importance in classification.
Subsequent writers have, for the most part, increased the number of recognized orders; and during the last few years several schemes of classification have been published, in the most revolutionary of which - that of A.
The classification here adopted is based on Sharp's scheme, with the addition of suggestions from some of the most recent authors - especially Bdrner and Enderlein.
Geological History The classification just given has been drawn up with reference to existing insects, but the great majority of the extinct forms that have been discovered can be referred with some confidence to the same orders, and in many cases to recent families.
The first is entitled Externarum et internarum principalium humani corporis Tabulae, &c. while the second, which is the most valuable, is merely appended to the Lectiones Gabrielis Fallopii de partibus similaribus humani corporis, &c., and thus, the scope of each work being regarded as medical, the author's labours were wholly overlooked by the mere naturalhistorians who followed, though Coiter introduced a table, " De differentiis Auium," furnishing a key to a rough classification of such birds as were known to him, and this as nearly the first attempt of the kind deserves notice here.
In his classification of birds Linnaeus for the most part followed Ray, and where he departed from his model he seldom improved upon it.
His attempt at classification was certainly better than that of Linnaeus; and it is rather curious that the researches of the latest ornithologists point to results in some degree comparable with Brisson's systematic arrangement, for they refuse to keep the birds-of-prey at the head of the Class A y es, and they require the establishment of a much larger number of " Orders " than for a long while was thought advisable.
The classification was modified, chiefly on the old lines of Willughby and Ray, and certainly for the better; but no scientific nomenclature was adopted, which, as the author subsequently found, was a change for the worse.
He took many liberties with the details of Linnaeus's work, but left the classification, at least of the birds, as it was - a few new genera excepted.'
5 Though he made a perceptible advance on the classification of Linnaeus, at that time predominant, it is now easy to see in how many ways - want of sufficient material being no doubt one of the chief - Cuvier failed to produce a really natural arrangement.
In the work just mentioned few details are given; but even the more elaborate classification of birds contained in his Lecons d'anatomie comparee of 1805 is based wholly on external characters, such as had been used by nearly all his predecessors; and the Regne Animal of 1817, when he 1 This was reprinted in 5882 by the Willughby Society.
5 It had no effect on Lacepbde, who in the following year added a Tableau methodique containing a classification of birds to his Discours d'ouverture (Mdm.
Unfortunately for him, as will appear in the sequel, it seems not to have occurred to him to use any of the results he obtained as the basis of a classification.
The more important monographs will usually be found cited in the separate articles on birds contained in this work, though some, by reason of changed views of classification, have for practical purposes to be regarded now as general works.
These need not detain us for long, since, however well some of them may have been executed, regard being had to their epoch, and whatever repute some of them may have achieved, they are, so far as general information and especially classification is concerned, wholly obsolete, and most of them almost useless except as matters of antiquarian interest.
The classification was quite new, and made a step distinctly in advance of anything.
In 1816 Vieillot published at Paris an Analyse d'une nouvelle ornithologie elementaire, containing a method of classification which he had tried in vain to get printed before, both in Turin and in London.
The views of neither of these systematizers pleased Temminck, who in 1817 replied rather sharply to Vieillot in some Observations sur la classification methodique des oiseaux, a pamphlet published at Amsterdam, and prefixed to the second edition m i nd.
erect a classification, that there was in them more of importance, hidden in the integument, than had hitherto been suspected; but the warning was of little avail, if any, till many years had elapsed.
However, Nitzsch had not as yet seen his way to proposing any methodical arrangement of the various groups of birds, and it was not until some eighteen months later that a scheme of classification in the main anatomical was attempted.
This is a very disappointing performance, since the author observes that, notwithstanding his new classification of birds is based on a study of the form of the sternal apparatus, yet, because that lies wholly within the body, he is compelled to have recourse to such outward characters as are afforded by the 1 From carin g, a keel.
251269) a statement of his general views on ornithological classification which were based on a comparative examination of those bodies in various forms. It seems unnecessary here to occupy space by giving an abstract of his plan, 8 which hardly includes any but European species, because it was subsequently elaborated with no inconsiderable modifications in a way that must presently be mentioned at greater length.
Two years later Nitzsch, who was indefatigable in his endeavour to discover the natural families of birds and had been pursuing a series of researches into their vascular system, published the result, at Halle in Saxony, in his Observationes de avium arteria carotide communi, in which is included a classification drawn up in accordance with the variation of structure which that important vessel presented in the several groups that he had opportunities of examining.
But it must be observed that the classification of Nitzsch, just given, rests much more on characters furnished by the general structure than on those furnished by the carotid artery only.
For the rest his classification demands no particular remark; but that in a work of this kind he had the courage to recognize, for instance, such a fact as the essential difference between swallows and swifts lifts him considerably above the crowd of other ornithological writers of his time.
An improvement on the old method of classification by purely external characters was introduced to the Academy of Sciences of Stockholm by C. J.
His scheme of classification, being as before stated partial, need not be given in detail.
But a bolder attempt at classification was that made in 1838 by Blyth in the New Series (Charlesworth's) of the Magazine of Natural History (ii.
In the same year (1839) another slight advance was made in the classification of the true Passerines.
4 This association is one of the most remarkable in the whole' series of Blyth's remarkable papers on classification in the volume cited above.
While furnishing - almost unconsciously, however - additional evidence for overthrowing that classification, there is, nevertheless, no attempt made to construct a better one; and the elaborate tables of dimensions, both absolute and proportional, suggestive as is the whole tendency of the author's observations, seem not to lead to any very practical result, though the systematist's need to look beneath the integument, even in parts that are so comparatively little hidden as birds' feet, is once more made beyond all question apparent.
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.
x.-xii.), while Blyth and Nitzsch had (as already mentioned) seen some of their value in classification.
It is now necessary to revert to the year 1842, in which Dr Cornay of Rochefort communicated to the French Academy of Sciences a memoir on a new classification of birds, of which, however, nothing but a notice has been preserved (Comptes rendus, xiv.
In the evolution of these laws Dr Cornay had most laudably studied, as his observations prove, a vast number of different types, and the upshot of his whole labours, though not very clearly stated, was such as to wholly subvert the classification at that time generally adopted by French ornithologists.
The same year which saw the promulgation of the crude scheme just described, as well as the publication of the final researches of Muller, witnessed also another attempt at the classification of birds, much more limited indeed in scope, but, so far as it went, regarded by most ornithologists of the time as almost final in its operation.
This will perhaps be the most convenient place to mention another kind of classification of birds, which, based on a principle wholly different from those that have just been explained, requires a few words, though it has not been productive, parte.
Blanchard published some Recherches sur les caracteres osteo- logiques des oiseaux appliquees a la classification naturelle de ces animaux, strongly urging the superiority of such characters over those drawn from the bill or feet, which, he remarks, though they may have sometimes given correct notions, have mostly led to mistakes, and, if observations of habits and food have sometimes afforded happy results, they have often been deceptive; so that, should more be wanted than to draw up a mere inventory of creation or trace the distinctive outline of each species, zoology without anatomy would remain a barren study.
Its basis is the classification of Cuvier, the modifications of which by Des Murs will seldom commend themselves to systematists whose opinion is generally deemed worth having.
Few, if any, of the faults of that classification are removed, and the improvements suggested, if not established by his successors, those especially of other countries than France, are ignored, or, as is the case with some of those of L'Herminier, are only cited to be set aside.
Classification assumed a wholly different aspect.
Classification for the first time was something more than the expression of a fancy, not that it had not also its imaginative side.
3 In reply to some critical remarks (Ibis, 1868, pp. 8 5-9 6), chiefly aimed at showing the inexpediency of relying solely on one set of characters, especially when those afforded by the palatal bones were not, even within the limits of families, wholly diagnostic, the author (Ibis, 1868, pp. 357-362) announced a slight modification of his original scheme, by introducing three more groups into it, and concluded by indicating how its bearings upon the great question of " genetic classification" might be represented so far as the different groups of Carinatae are concerned: - 1 These names are compounded respectively of Dromaeus, the generic name applied to the emeu, 7xQ-a, a split or cleft, SEVµa, a bond or tying, a finch, and, in each case, yvaBos, a jaw.
2 The notion of the superiority of the palatal bones to all others for purposes of classification has pleased many persons, from the fact that these bones are not unfrequently retained in the dried skins of birds sent home by collectors in foreign countries, and are therefore available for study, while such bones as the sternum and pelvis are rarely preserved.
For the development of this classification see Element.
This classification is founded on the kinds of problems arising from the combinations.
This is the great difficulty of classification.
More than this, he entered upon their geographical distribution, the facts of which important subject are here, almost for the first time, since the attempt of Blyth already mentioned, 4 brought to bear practically on classification.
Here we must mention the intimate connexion between classification and geographical distribution as revealed by the palaeontological researches of Alphonse Milne-Edwards, whose magnificent Oiseaux Fossiles de la France a.
Hence it became manifest that a very respectable classification can be found in which characters drawn from these bones play a rather important part.
Unfortunately none of these, however, can be compared for singularity with Archaeopteryx or with some American fossil forms next to be noticed, for their particular It is true that from the time of Buffon, though he scorned any regular classification, geographical distribution had been occasionally held to have something to do with systematic arrangement; but the way in which the two were related was never clearly put forth, though people who could read between the lines might have guessed the secret from Darwin's Journal of Researches, as well as from his introduction to the Zoology of the " Beagle" Voyage.
The former efforts at classification made by Sundevall have already several times been mentioned, and a return to their con sideration was promised.
Hence his efforts, praiseworthy as they were from several points of view, and particularly so in regard to some details, failed to satisfy the philosophic taxonomer when generalizations and deeper principles were concerned, and in his practice in respect of certain technicalities of classification he was, in the eyes of the orthodox, a transgressor.
Later systems of classification owe much to anatomy, and the pioneers in the modern advances in this respect were A.
the classification of birds, although the material they furnished and the lines they indicated have proved valuable in later hands.
Sclater published in the Ibis a classification which was mainly a revision of the system of Huxley, modified by the investigations of Garrod and Forbes and by his own large acquaintance with museum specimens.
Reichenow in Die Vogel der zoologischen Garten published a classification of birds with a phylogenetic tree.
Apart from its intrinsic merits as a learned and valuable addition to classification, this work is interesting in the history of ornithology because of the wholesale changes of nomenclature it introduced as the result of much diligence and zeal in the application of the strict rule of priority to the names of birds.
The system of classification adopted in time became so elaborate that many municipalities became isolated, each in a separate class, and the evils of special legislation were revived.
Meanwhile the English naturalist, John Ray, was studying the classification of animals; he published, in 1705, his Methodus insectorum, in which the nature of the metamorphosis received due weight.
In the realm of classification, the work of Linnaeus was continued in Denmark by J.
Westwood (Modern Classification of Insects, 1839-1840) connects these older writers with their successors of to-day.
Considerable difficulty is encountered in attempting to draw up a botanical classification of the species of Gossypium.
The situation of the lateral nervestems in the different genera with respect to the muscular layers lends definite support to the interpretation of their homologies here given and forms the basis of Burger's classification.
In the second classification (2) is typical of the " cold " process, whilst (I), (3), (4) are effected by the, boiling " process.
They are broken up into almost countless tribes and clans, many of which number only a few hundred individuals, and their language consequently presents a variety of dialects, of which no classification has yet been effected: in the district of Posia alone a member of the Presbyterian mission distinguished eight different mutually unintelligible dialects.
His name is best known for the share he had in the periodic classification of the elements.
For the morphology and classification of snails, see Gastropoda.
Consequently we are justified in retaining "Ratitae" in our classification, although they are a heterogeneous, not strictly monophyletic, assembly.
To the physicist matter is presented in three leading forms - solids, liquids and gases; and although further subdivisions have been rendered necessary with the growth of knowledge the same principle is retained, namely, a classification based on properties having no relation to composition.
The fundamental chemical classification of matter, on the other hand, recognizes two groups of substances, namely, elements, which are substances not admitting of analysis into other substances, and compounds, which do admit of analysis into simpler substances and also of synthesis from simpler substances.
Carbon was joined with silicon, zirconium and titanium, while boron, being trivalent, was relegated to another group. A general classification of elements, however, was not realized by Frankland, nor even by Odling, who had also investigated the question from the valency standpoint.
It is true that by the distillation of many herbs, resins and similar substances, several organic compounds had been prepared, and in a few cases employed as medicines; but the prevailing classification of substances by physical and; superficial properties led to the correlation of organic and inorganic compounds, without any attention being paid to their chemical composition.
The clarification and spirit of research so clearly emphasized by Robert Boyle in the middle of the 17th century is reflected in the classification of substances expounded by Nicolas Lemery, in 1675, in his Cours de chymie.
Notwithstanding the inconsistency of his allocation of substances to the different groups (for instance, acetic acid was placed in the vegetable class, while the acetates and the products of their dry distillation, acetone, &c., were placed in the mineral class), this classification came into favour.
At the same time, however, he adhered to the classification of Lemery; and it was only when identical compounds were obtained from both vegetable and animal sources that this subdivision was discarded, and the classes were assimilated in the division organic chemistry.
Classification of Organic Compounds.
This description, although not absolutely comprehensive, serves as a convenient starting-point for a preliminary classification, since a great number of substances, including the most important, are directly referable to hydrocarbons, being formed by replacing one or more hydrogen atoms by other atoms or groups.
From these nuclei an immense number of derivatives may be obtained, for the hydrogen atoms may be substituted by any of the radicals discussed in the preceding section on the classification of organic compounds.
The development of the theory of crystal structure, and the fundamental principles on which is based the classification of crystal forms, are treated in the article Crystallography; in the same place will be found an account of the doctrine of isomorphism, polymorphism and morphotropy.
A comparison of the transformation of polymorphs leads to a twofold classification: (1) polymorphs directly convertible in a reversible manner - termed " enantiotropic " by O.
Isomorphism is most clearly discerned between elements of analogous chemical properties; and from the wide generality of such observations attempts have been made to form a classification of elements based on isomorphous replacements.
Again, as Romulus was the author of the patrician groundwork of the constitution, so Servius was regarded as the originator of a new classification of the people, which laid the foundation of the gradual political enfranchisement of the plebeians (for the constitutional alterations with which his name is associated, see Rome: Ancient History; for the Servian Wall see Rome: Archaeology).
Lee) was issued, the simple classification of sporting and non-sporting dog - terriers and toy dogs, being adopted; but although there had been an understanding since 1874, when the first volume of the Kennel Club Stud Book (Frank C. S.
All these varieties were represented at the annual show of the Kennel Club in the autumn of 1905, and at the representative exhibition of America held under the management of the Westminster Kennel Club in the following spring the classification was substantially the same, additional breeds, however, being Boston terriers - practically unknown in England, - Chesapeake Bay dogs, Chihuahuas, Papillons and Roseneath terriers.
The latter were only recently introduced into the United States, though well known in Great Britain as the West Highland or Poltalloch terrier; an application which was made (1900) by some of their admirers for separate classification was refused by the Kennel Club, but afterwards it was granted, the breed being classified as the West Highland white terrier.
No scientific classification of the breeds of dogs is at present possible, but whilst the division already given into "sporting" and "non-sporting" is of some practical value, for descriptive purposes it is convenient to make a division into the six groups: - wolfdogs, greyhounds, spaniels, hounds, mastiffs and terriers.
Considerable difference of opinion exists with regard to the best classification of the family, some authorities including most of the species in the typical genus Rhinoceros, while others recognize quite a number of sub-families and still more genera.
A complete classification of mathematical sciences, as they at present exist, is to be found in the International Catalogue of Scientific Literature promoted by the Royal Society.
The classification in question was drawn up by an international committee of eminent mathematicians, and thus has the highest authority.
The practical object of the enterprise required that the proportionate quantity of yearly output in the various branches, and that the liability of various topics as a matter of fact to occur in connexion with each other, should modify the classification.
His mode of viewing Christianity does not fit into any classification.
The complexity of composition militates in a great measure against a rational classification of albumins by purely chemical considerations.
P. Pick; but in the present state of our knowledge, however, p g > the older classification of E.
This classification is with certain modifications as follows: I.
One classification makes three divisions for the epoch, characterized respectively by the existence of the cavebear, the mammoth and reindeer; another, two, marked by the prevalence of the mammoth and reindeer respectively.
The following scheme of classification is based on Beecher's and Schubert's.
As a member of the state Senate he supported the War of 1812 and drew up a classification act for the enrolment of volunteers.
This fact renders their association with the Crustacea impossible, if classification is to be the expression of genetic affinity inferred from structural coincidence.
We have now to offer a classification of the Arachnida and to pass in review the larger groups, with a brief statement of their structural characteristics.
Tabular Classification 1 Of The Arachnida.
The greater or less evolution and specialization of the metasomatic carapace appears to be the most important basis for classification - but this has not been made use of in the latest attempts at drawing up a system of the Trilobites.
Pocock, assistant in the Natural History departments of the British Museum, for valuable assistance in the preparation of this article and for the classification and definition of the groups of Eu-arachnida here given.
Claus, " Degeneration of the Acari and Classification of Arthropoda," Anzeiger d.
Berlin, 1861; Pocock, " Classification of Scorpions," Ann.
(London, 1899); Keyserling, Spinnen Amerikas (Nuremberg, 1880-1892); Pocock, " Liphistius and the Classification of Spiders," Ann.
Soc., 1894; Nalepa, " Phytoptidae," Das Thierreich (Berlin, 1898); Trouessart, " Classification des Acariens," Rev. Sci.
It is hardly possible to form any classification which is not open to some objection.
In any case the classification must be to some extent provisional, since scholars are still divided as to the original language, date and place of composition of some of the books which must come under our classification.'
The interesting problem of the future is - are we to regard this classification as fixed or as merely transitory?
Meckel, 3 on the other hand, while equally accepting Brongniart's classification, retained the term Amphibia in its earlier Linnaean sense; and his example has been generally followed by German writers, as, for instance, by H.
More 1 Brongniart's Essai d'une classification naturelle des reptiles was not published in full till 1803.
Latreille 6 published a new classification of the Vertebrata, which are primarily divided into Haematherma, containing the three classes of Maminifera, Monotremata and A y es; and Haemacryma, also containing three classes - Reptilia, Amphibia and Pisces.
In most cases these subsidiary algebras, as they may be called, are inseparable from the applications in which they are used; but in any attempt at a natural classification of algebra (at present a hopeless task), they would have to be taken into account.
Rating, in maritime vocabulary, is the classification of men according to rank, and was formerly employed to class ships of a navy according to strength.
The classification of ships into six rates, and into rated and non-rated ships, continued during the existence of the old sailing fleets, with modifications in detail.
Systems Of Classification Morphography includes the systematic exploration and tabulation of the facts involved in the recognition of all the recent and extinct kinds of animals and their distribution in space and time.
Aristotle did not definitely and in tabular form propound a classification of animals, but from a study of his treatises Historia animalium, De generatione animalium, and De partibus animalium the following classification can be arrived at: - A.
By the introduction of a method of classification which was due to the superficial Pliny - depending, not on structure, but on the medium inhabited by an animal, whether earth, air or waterWotton is led to associate Fishes and Whales as aquatic animals.
extended until it formed a sufficient body of knowledge to serve as an anatomical basis for classification.
Apart from his special discoveries in the anatomy of plants and animals, and his descriptions of new species, the great merit of Linnaeus was his introduction of a method of enumeration and classification which may be said to have created systematic zoology and botany in their present form, and establishes his name for ever as the great organizer, the man who recognized a great practical want in the use of language and supplied it.
The classification of Linnaeus (from Syst.
His classification (1801-1812) is as follows: - Class V.
It was in 1812 that Cuvier communicated to the Academy of Sciences of Paris his views on the classification of animals.
Cuvier's His classification as finally elaborated in Le Regne classifi- cation.
The classification adopted by Owen in his lectures (1855) does not adequately illustrate the progress of zoological classifi- knowledge between Cuvier's death and that date, but, such as it is, it is worth citing here.
The wave of morphological speculation, with its outcome of new systems and new theories of classification.
His most important memoirs, besides that just mentioned, are those on the anatomy and classification of Fishes, on the Caecilians and on the developmental history of the Echinoderms.
It is impossible to enumerate or to give due consideration to all the names in the army of anatomical and embryological students of the middle third of the 19th century whose labours bore fruit in the modification of zoological theories and in the building up of a true classification of animals.
Their results are best summed up in the three schemes of classification which follow below - those of Rudolph Leuckart (1823-1896), Henri Milne-Edwards (1800-1884), and T.
Contemporaneous with these were various schemes of classification which were based, not on a consideration of the entire structure of each animal, but on the variations of a single organ, or on the really non-significant fact of the structure of the egg.
Leuckart's classification (Die Morphologic and die Verwandtschaftsverhaltnisse der wirbellosen Thiere, 'lassifi- ' ation.
(Not specially dealt with.) Mll°e" The classification given by Henri Milne-Edwards i Elementaire d'Histoire Naturelle, Paris, 1855) is as follows: - Branch I.
Huxley adopted in his lectures (1869) a classification which was in many respects similar to both of the foregoing, but embodied improvements of his own.
We now arrive at the period when the doctrine of organic evolution was established by Darwin, and when naturalists, being convinced by him as they had not been by the transmutationists of fifty years' earlier date, were compelled to take an entirely new view of the significance of all attempts at framing a " natural " classification.
From time to time efforts were made by those who believed that the Creator must have followed a symmetrical system in his production of animals to force one or other artificial, neatly balanced scheme of classification upon the zoological world.
That doctrine took some few years to produce its effect, but it became evident at once to those who accepted Darwinism that the natural classification of animals, after which collectors and anatomists, morphologists, philosophers and embryologists had been so long striving, was nothing more nor less than a genealogical tree, with breaks and gaps of various extent in its record.
1834), who in 1866, seven years after the publication of Darwin's Origin of Species, published his suggestive Generelle Morphologic. Haeckel introduced into classification a number of terms intended to indicate the branchings of a genealogical tree.
The whole " system " or scheme of classification was termed a genealogical tree (Stammbaum); the main branches were termed " phyla," their branchings " sub-phyla "; the great branches of the sub-phyla were termed " cladi," and the " cladi " divided into " classes," these into sub-classes, these into legions, legions into orders, orders into sub-orders, suborders into tribes, tribes into families, families into genera, genera into species.
Haeckel's classification of 1866 was only a first attempt.
In the edition of the Natiirliche Schopfungsgeschichte published in 1868 he made a great advance in his genealogical classification, since he now introduced the results of the extraordinary activity in the study of embryology which followed on the publication of the Origin of Species.
Balfour, and produced the profoundest modifications in classification.
The term " grade " was introduced by Ray Lankester (" Notes on Embryology and Classification," in Quart.
Another important factor in the present condition of zoological knowledge as represented by classification is the doctrine of degeneration propounded by Anton Dohrn.
1 It is to be noted that the terms used for designating categories in the classification are not always identical in this summary and separate articles, as authors differ as to the use of these.
The immediate result was, as pointed out above, a reconstruction of the classification of animals upon a genealogical basis, and an investigation of the individual development of animals in relation to the steps of their gradual building up by cell-division, with a view to obtaining evidence of their genetic relationships.
The most instructive classification of the " variations " exhibited by fully formed organisms consists in the separation in the first place of those which arise from antecedent congenital, innate, constitutional or germinal variations from those which arise merely from the operation of variation of the environment or the food-supply upon normally constituted individuals.
To meet this exigency, Zarlino proposed that for the lute the octave should be divided into twelve equal semitones; and after centuries of discussion this system of "equal temperament" has, within the last thirty-five years, been universally adopted as the best attainable for keyed instruments of every description.3 Again, Zarlino was in advance of his age in his classification of the ecclesiastical modes.
Otric, suspecting that Gerbert erred in his classification of the sciences, sent one of his own pupils to Reims to take notes of his lectures, and, finding his suspicions correct, accused him of his error before Otto II.
The latest classification of Molengraaff subdivides the beds as follows: - Beaufort beds of Cape Colony.
Details of the morphology of plants will be found in the articles relating to the chief groups of plants, those of animals in the corresponding articles on groups of animals, while the classification of animals adopted in this work will be found in the article ZOOLOGY.
This classification is ingenious and convenient as far as it goes, but it seems probable that the trouser, which also has the waist as its point of attachment, may itself be a further development of the girdle.
It reported favourably, especially on the use of the measurements for primary classification, but recommended also the adoption in part of a system of "finger prints" as suggested by Francis Galton, and already practised in Bengal.
It is largely to researches on the bone marrow that we owe our present knowledge of the origin and the classification of the different cellular elements of the blood, both erythrocytes or red corpuscles, and the series of granular leucocytes or white corpuscles.
Cullen drew out a classification of great and needless complexity, the chief part of which is now forgotten, but several of his main divisions are still preserved.
We must retrace our steps a little to enumerate several distinguished names which, from the nature of the case, hardly admit of classification.
de Lacroix (1706-1767), gave, under the title Nosologia methodica, a natural-history classification of diseases; Jean Astruc (1684-1766) contributed to the knowledge of general diseases.
With the melting of the ice the more daring spirits dashed into the new current with such ardour that for them all traditions, all institutions, were thrown into hotchpot; even elderly and sober physicians took enough of the infection to liberate their minds, and, in the field of the several diseases and in that of post-mortem pathology, the hollowness of classification by superficial resemblance, the transitoriness of forms, and the flow of processes, broke upon the view.
In his classification it was included in the same genus as the orang-utan; and it has recently been suggested that the name Simia pertains of right to the chimpanzee rather than to the orang-utan.
Looking somewhat deeper at the sources from which Old English law was derived, we shall have to modify our classification to some extent, as the external forms of publication, although important from the point of view of historical criticism, are not sufficient standards as to the juridical character of the various kinds of material.
ments of custom included in the second division according to the first classification, a great many of the rules entered in collections promulgated by kings; most of the paragraphs of iEthelberht's, Hlothhere's, and Eadric's and Ine's laws, are popular legal customs that have received the stamp of royal authority by their insertion in official codes.
Classification of the Cestoda Merozoa [[Order I]].
Havana cigars are, as regards form, classification, method of putting up and nomenclature, the models followed by manufacturers of all classes of the goods.
In its chemical relations, titanium is generally tetravalent, and occurs in the same sub-group of the periodic classification as zirconium, cerium and thorium.
- For general accounts of the structure and development of the Polyzoa the reader's attention is specially directed to 12, 14, 6, 25, I, 2, 17, 26, 18, 23, 3, in the list given below; for an historical account to i; for a full bibliography of the group, to 22; for fresh-water forms, to 1-3, 7-10, 17; for an indispensable synonymic list of recent marine forms, to 15; for Entoprocta, to to, II, 24; for the classification of Gymnolaemata, to 21, 1 4, 4, 13, 20; for Palaeontology, to 27, 22.
The first step in this direction is to arrange scientific method and positive knowledge in order, and this brings us to another cardinal element in the Comtist system, the classification of the sciences.
Comte's principle of classification is that the dependence and order of scientific study follows the dependence of the phenomena.
Comte's classification of the sciences has been subjected to a vigorous criticism by Herbert Spencer.
The isomerism which occurs as soon as the molecule contains a few carbon atoms renders any classification based on empirical molecular formulae somewhat ineffective; on the other hand, a scheme based on molecular structure would involve more detail than it is here possible to give.
The classification of snakes has undergone many vicissitudes.
The classification of the animal kingdom is dealt with in the article ZOOLOGY.
- For the purpose of classification it will be convenient to discuss Lutheran, Zwinglian and Calvinistic confessions separately.
The rapid growth of literature in the 16th century compels him to resort to a classification of subjects.
b djv, a membrane, and 7rrepov, a wing), a term used in zoological classification for one of the most important orders of the class Hexapoda.
The main median nervure, and usually also the sub-costal become united with the radial, while the branches of radial, median and cubital nervures pursuing a transverse or recurrent course across the wing, divide its area into a number of areolets or " cells," that are of importance in classification.
In his recent classification Ashmead (1901) recognizes seventy-nine families arranged under eight " super-families."
rtµc-, half and irmpov, a wing), the name applied in zoological classification to that order of the class Hexapoda (q.v.) which includes bugs, cicads, aphids and scaleinsects.
The voyage of the " Challenger " supplied for the first time the nucleus of a collection of deep-sea deposits sufficient to serve as the basis for comprehensive classification and mapping.
The classification adopted was a double one, taking account both of the origin and of the distribution in depth of the various deposits, thus: - II.
The classification of the different kinds of coal may be considered from various points of view, such as their chemical composition, their behaviour when subjected to heat aa s sifica= or when burnt, and their geological position and iron.
As the amount of ash varies very considerably in different coals, and stands in no relation to the proportion of the other constituents, it is necessary in forming a chemical classification to compute the results of analysis after deduction of the ash and hygroscopic water.
Coal as raised from the pit is now generally subjected to some final process of classification and cleaning before being despatched to the consumer.
As regards classification, the first group is that of the Pecora, or Cotylophora, in which the cheek-teeth are selenodont, but there are no upper incisors or canine-like premolars, Pecora.
Although disposed at first to divide the various documents into three classes, he finally adopted a classification into two - the African or older family of documents, and the Asiatic, or more recent class, to which he attached only a subordinate value.
(Berlin, 1899); and the classification and phylogeny are considered by E.
His idea of applying the natural history method of classification to psychical phenomena gave scientific character to his work, the value of which was enhanced by his methodical exposition and his command of illustration.
praedicabilis, that which may be stated or affirmed), in scholastic logic, a term applied to a classification of the possible relations in which a predicate may stand to its subject.
The list given by the schoolmen and generally adopted by modern logicians is based on the original fivefold classification given by Aristotle (Topics, a iv.
There is, however, a radical difference between the two systems. The standpoint of the Aristotelian classification is the predication of one universal concerning another.
The Aristotelian classification may be briefly explained: (r) The Definition of anything is the statement of its essence (Arist.
in fixing the genus of a thing, we subsume it under a higher universal, of which 1 Strictly Aristotle's classification is into four as S&acbopa really belongs to ybvor.
This classification, though it is of high value in the clearing up of our conceptions of the essential contrasted with the accidental, the relation of genus, differentia and definition and so forth, is of more significance in connexion with abstract sciences, especially mathematics, than for the physical sciences.
Apart from one or two of the greatest minds, notably Dante, what appealed to the thinkers of the middle ages was not the idea of reality as a progressive self-revelation of an inner principle working through nature and human life, but the formal principles of classification which it seemed to offer for a material of thought and action given from another source.
(1903) of HauckHerzog's Realencyklopadie where the following classification is adopted: (a) exegetical, (b) scholia on the Fathers, (c) dogmatic and controversial, (d) ethical and ascetic, (e) miscellaneous.
With the increase of the city the operation grew in importance, and was followed by an official lustruni, or purificatory sacrifice, offered on behalf of the people by the censors or functionaries in charge of the classification.
Nor should it be forgotten that the internal classification and the combinations of the above subjects are also matters to be treated upon some uniform plan, if the full value of the statistics is to be extracted from the raw material.
In 1800 and 1810 the same classification was preserved, except that five age-groups instead of two were given for free white males and the same five were applied also to free white females.
In 1820 a sixth age class was introduced for free white males, an age classification of four periods was applied to the free coloured and the slaves of each sex, and the number of aliens and of persons engaged in agriculture, in manufactures and in commerce was called for.
It was also the first American census to give a line of the schedule to each person, death or establishment enumerated, and thus to make the returns in the individual form indispensable for a detailed classification and compilation.
The above classification relates to methods.
The classification of results, i.e.
His chief works were First Lines of the Practice of Physic (1774); Institutions of Medicine (1770); and Synopsis Nosologicae Medicae (1785), which contained his classification of diseases into four great classes - (t) Pyrexiae, or febrile diseases, as typhus fever; (2) Neuroses, or nervous diseases, as epilepsy; (3) Cachexiae, or diseases resulting from bad habit of body, as scurvy; L and (4) Locales, or local diseases, as cancer.
This classification of the members into those who were in full communion and those who belonged only to the " Half Way Covenant " was vigorously attacked by Jonathan Edwards, but it was not abolished until the early years of the 19th century.
Philosophy itself is with him classification and consideration of ideas.
Cities are of three classes: (1) those having a population of 175,000 or more; (2) those having a population between 50,000 and 175,000; and (3) those whose population is less than 50,000; the classification is according to the latest state enumeration.
For the classified service of the state and of the minor civil divisions, except cities, the commission makes rules (subject to the governor's approval and to statutory and constitutional provisions) governing the classification of offices, the examination of candidates for office, and the appointment and promotion of employees.
A small deduction should be made from this apparent increase to allow for a changed system of classification.
According to the 1904 census classification the " aboriginal inhabitants" numbered in that year 229,149.
Any division or classification of states must be imperfect.
Jellinek has suggested this classification (Die Lehre von den Staatenverbindungen, p. 58): (a) Unorganized associations, including - (1) treaties; (2) occupation of the territory of one state and administration by another, as in Bosnia and Cyprus; (3) alliances; (4) protectorates, guarantees, perpetual neutrality; (5) Der Staatenstaat, the feudal state, of which Jellinek gives the Turkish Empire and the old Holy Roman Empire as examples.
Waddell (De Pontibus, New York, 1898) proposes to arrange railways in seven classes, according to the live loads which may be expected from the character of their traffic, and to construct bridges in accordance with this classification.
The first thing noticeable about him is that he defies all customary and mechanical classification.
The Laksana Phra Thamasat, the Phra Tamra, Phra Tamnon, Phra Racha Kamnot and Inthapat are ancient works setting forth the laws of the country in their oldest form, adapted from the Dharmacastra and the Classification of the Law of Manu.
,It embraces a consideration of the external forms of plants - of their anatomical structure, however minute - of the functions which they perform - of their arrangement and classification - of their distribution over the globe at the present and at former epochs - and of the uses to which they are subservient.
Plants which were strikingly alike were placed together, but there was at first little attempt at systematic classification.
In 1690 Rivinus 2 promulgated a classification founded chiefly on the forms of the flowers.
A new era dawned on botanical classification with the work of Antoine Laurent de Jussieu (1748-1836).
Robert Brown (1773-1858) was the first British botanist to support and advocate the natural system of classification.
The study of the anatomy and physiology of plants did not keep pace with the advance in classification.
His followers were chiefly engaged in the arrangement and classification of plants, and while descriptive botany made great advances the physiological department of the science was neglected.
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.
Systematio, the arrangement and classification of plants (see Plants: Classification).
The latest authorities for description and classification of the genus are J.
classification) is one of abstraction.
Bird: Classification; and Ratitae).
Parker ("On the Cranial Osteology, Classification and Phylogeny of the Dinornithidae," Tr.
Systems of classification of flowers according to the agency by which pollination is effected have been proposed by Delpino, H.
Thorell's classification (1859) of Gnathostonta, Poecilostoma, Siphonostoma, based on the mouth-organs, was long followed, though almost at the outset shown by Claus to depend on the erroneous supposition that the Poecilostoma were devoid of mandibles.
The classification is worked out as follows: 1.
D.) Islands Of The Pacific Ocean Up to a certain point, the islands of the Pacific fall into an obvious classification, partly physical, partly political.
Moreover usage varies slightly as regards the limits of the three main divisions, but the accompanying table shows the most usual classification, naming the principal groups within each, and distributing them according to the powers to which they are subject.
The municipalities are divided into six classes according to population, a classification which permits considerable special local legislation in spite of the constitutional inhibition.
The general appearance is too misleading for the classification of the Lacertae.
5, xiv., 1884, p. 117, &c.) has further improved upon the then prevailing arrangements, and has elaborated a classification which, used by himself in the three volumes of the catalogue of lizards in the British Museum, is followed in the present article with slight alterations in the order of treatment of the families.
Materials accumulated far more rapidly, however, than the power of generalization and classification.
Able as von Meyer was, his classification of the Reptilia failed because based upon the single adaptive characters of foot structure.
In Kowalevsky's Versuch einer natiirlichen Classification der Fossilen Hufthiere (1873) we find a model union of detailed inductive study with theory and working hypothesis.
From the stomach, canals arise termed the radial canals (r.c.); typically four in number, they run in a radial direction to the edge 2 For other variations of the medusa, often of importance for systematic classification, see Hydromedusae and Scyphomedusae.
This classification of the Nahuatlac tribes has a meaning and value.
The following classification of rotifers is our modification of that of Hudson and Gosse, further altered through considerations put From H.
Hudson and Gosse containing a new classification, an illustrated description of all the then known species and much information on habits and structure, provided students with an easy access to the domain and stimulated many to work hard at the group. Of these new-corners we may cite C. F.
It is probable that no satisfactory classification of the Trilobites will be proposed until the limbs of most of the genera have been examined.
We distinguish between animate and inanimate nature, but this classification has no meaning for the savage.
The term is synonymous with Cryptogams, by which it was replaced in later systems of classification.
The classification in the right-hand column of this table is not applicable in detail to regions remote from New York.
The classification of the system in New York is as follows:
This older classification, which has little support except that which is traditional, is still adhered to by many geologists; hut the fact seems to be that the system is set off from the Pennsylvanian (Upper Carboniferous) more sharply than the Cambrian is from the Ordoviciao, the Silurian from the Devonian, or the Devonian from the Mississippian.
The classification of the Eocene (and Oligocene) formations in the Gulf region, especially east of the Mississippi, is as follows:
This classification is based almost wholly on the fossils, for there seems to be little physical reason for the differentiation of the Oligocene anywhere on the continent.
The number and classification of these departments vary widely in the different cities.
A chemical classification of alkaloids is difficult on account of their complex constitution.
The following classification is simple and convenient; the list of alkaloids makes no pretence at being exhaustive.
The former classification based on these differences in the adductor muscles is now abandoned, having proved to be an unnatural one.
followed out by Dr Paul Pelseneer in the classification now generally adopted.
Classification Of Lamellibranchia The classification originally based on the structure of the gills by P. Pelseneer included five orders, viz.: the Protobranchia in which the gill-filaments are flattened and not reflected; the Filibranchia in which the filaments are long and reflected, with non-vascular junctions; the Pseudo-lamellibranchia in which the gill-lamellae are vertically folded, the interfilamentar and interlamellar junctions being vascular or non-vascular; the Eulamellibranchia in which the interfilamentar and interlamellar junctions are vascular; and lastly the Septibranchia in which the gills are reduced to a horizontal paltition.
He arrives at it from a classification of categories, by which he here means " things stated in no combination " era KaTa pr)bEpiav avparro,c v XeyoµEva) or what we should call " names," capable of becoming predicates (KaT'gyopovpeva, Karnyopiac).
Both works arrive at it from the classification of categories, which is the same in both; except that in the former the categories are treated rather as a logical classification of names signifying things, in the latter rather as a metaphysical classification of things.
In neither, however, are they a grammatical classification of words by their structure; and in neither are they a psychological classification of notions or general conceptions (voi uara), such as they afterwards became in Kant's Critique and the post-Kantian idealism.
Aristotle calls all these investigations sciences (brcaT7)µac); but he also uses the term " sciences " in a narrower sense in consequence of a classification of their objects, which pervades his writings, into things necessary and things contingent, as follows: (A) The necessary (TO iv5Ex6yEvov i.AAws 'xEtv), what must be; subdivided into: (1) Absolutely (airX&os), e.g.
3), and in the classification would stop at mathematics, which we still call exact science: in the wide sense, on the other hand, it extends to the whole of the necessary and to the usual contingent, but excludes the accidental (Met.
E 2), and would in the classification include not only metaphysics and mathematics, but also physics, ethics, economics, politics, necessary and fine art; or in short.
This is the real order of Aristotle's system, based on his own theory and classification of sciences.
So far from coming first, Logic comes nowhere in his classification of science.
Secondly, he made no division of logic. In the Categories he distinguished names and propositions for the sake of the classification of names; in the De Interpretatione he distinguished nouns and verbs from sentences with a view to the enunciative sentence: in the Analytics he analysed the syllogism into premisses and premisses into terms and copula, for the purpose of syllogism.
He really left the Peripatetics to combine his scattered discourses and treatises into a system, to call it logic, and logic Organon, and to put it first as the instrument of sciences; and it was the Stoics who first called logic a science, and assigned it the first place in their triple classification of science into logic, physics, ethics.
The Analytics then, which from the beginning claims to deal with science, is a science of sciences, without however forming any part of the classification.
the Metaphysics, the Nicomachean Ethics, the Rhetoric; and above all teach his whole system as far as possible in the real order of his classification of science.
THE Aristotelian Philosophy We have now (r) sketched the life of Aristotle as a reader and a writer from early manhood; (2) have watched him as a Platonist, partly imitating but gradually emancipating himself from his master to form a philosophy of his own; (3) have traced the gradual composition of his writings from Plato's time onwards; (4) have distinguished earlier, more Platonic and rudimentary, from later, more independent and mature, writings; (5) have founded the real order of his writings, not on chronology, nor on tradition, but on his classification of science and learning.
We shall begin therefore with that primary philosophy which is the real basis of his philosophy, and proceed in the order of his classification of science to give his chief doctrines on: (1) Speculative philosophy, metaphysical and physical, including his psychology, and with it his logic.
veupov, a nerve, and 7rmEp6v, a wing), a term used in zoological classification for an order of the class Hexapoda.
All such families - falling into the group Exopterygota as defined in the classification of the Hexapodawere separated from the Neuroptera by W.
But if classification is to express relationship, it is impossible to associate in the same order families whose kinship to insects of other orders is nearer than their kinship to each other.
The place which it almost at once took among scientific scholars in Great Britain and throughout Europe was a recognition of the great advance which it represented in the use and classification of ancient authorities.
It is a member of the sixth group in the periodic classification of the elements, being included in the natural family of elements containing molybdenum, tungsten and uranium.
Further details in regard to this, the last revolution in Molluscan classification, will be found in the article Polyzoa.
All rodents are vegetable-feeders, and this uniformity in their food and in the mode of obtaining it, namely by gnawing, has led to that general uniformity in structure observable throughout the group; a feature which renders their classification difficult.
Some diversity of view obtains among naturalists with regard to the classification of the order; the scheme here followed being the one adopted (with some modifications of nomenclature) by Professor Max Weber in his Sliugethiere.
In 1899 Dr Forsyth Major proposed a classification of the family in which a number of species were grouped with the spiny rabbit in the genus Caprolagus, whilst Oryctolagus was taken to include not only the common rabbit, but likewise the Cape hare.
A more recent classification is that of Mr M.
Forsyth-Major, "On some Miocene Squirrels, with Remarks on the Dentition and Classification of the Sciuridae," Proc. Zool.
Lyon, "Classification of the Hares and their Allies," Smithsonian Miscell.
E '7r1, on, and ypb4av, to write), a term used to denote (1) the study of inscriptions collectively, and (2) the science connected with the classification and explanation of inscriptions.
The object of the provision, however, has been in a large measure nullified by the system of city classification, under which Philadelphia is the only city of the first class.
For convenience of classification we may include in Khamdo a long strip of country extending along the northern border of the Lhasa territory of Lhorong jong and Larego as far as Tengri Nor, and bounded to the north by the Dang-la mountains, which is designated by Tibetans as Gyade or " the Chinese province."
606s, straight, and irrepOv, a wing), a term used in zoological classification for a large and important order of the class Hexapoda.
Those who wish to follow out the classification in detail should refer to some of the recent monographs mentioned below in the bibliography.
The perithecium is very constant in form and since the gonidia take no part variations are of value in classification some more details may be added.
The classification of lichens is unique in the fact that chemical colour reactions are used by many lichenologists in the discrimination of species, and these reactions are included in the specific diagnoses.
Considerations such as these should make one very wary in placing reliance on these colour reactions for the purposes of classification.
A brief outline of a system of classification, mainly that of Zahlbruckner as given in Engler and Prantl's Pjlanzenfamilien, is outlined below.
Classification of the Neomeniomorpha.
In Europe, the system is very completely developed in the British Isles, where was made the first successful attempt at a classification of its various members, although at a somewhat earlier date Omalius d'Halloy had recognized a terrain bituminifere or coal-bearing series in the Belgian region.
Whether a spore results from the sexual union of two similar gametes (zygospore) or from the fertilization of an egg-cell by the protoplasm of a male organ (oospore); or is developed asexually as a motile (zoospore) or a quiescent body cut off from a hypha (conidium) or developed along its course (oidium or chlamydospore), or in its protoplasm (endospore), are matters of importance which have their uses in the classification and terminology of spores, though in many respects they are largely of academic interest.
The chief schemes of classification put forward in detail have been those of P. A.
The real difficulty of classification of the fungi lies in the polyphyletic nature of the group. There is very little doubt that the primitive fungi have been derived by degradation from the lower algae.
A natural classification on these lines would obviously be very complicated, so that in the present state of our knowledge it will be best to retain the three main groups mentioned above,.
The classification of the Mucorini depends on the prevalence and characters of the conidia, and of the sporangia and zygospores - e.g.
Classification: van Tieghem, Journ.
- General Classification of Iron and Steel according (I) to Carbon-Content and (2) to Presence or Absence of Inclosed Slag.
This classification was based on carbon-content, or on the properties which it gave.
This classification, though it helps to give a general idea of the subject, yet like most of its kind cannot be applied rigidly.
Some odd lots of skins arrive designated simply as "sundries," so no classification is possible, and this will account for the absence of a few names of skins of which the imports are insignificant in quantity, or are received direct by the wholesale merchants.
Bacher, Berlin, 1888), was marked by methodical comprehensiveness, and introduced into the theory of the verbs a new classification of the stems which has been retained by later scholars.
Early writers on natural history used the term in its vague logical sense without limiting it to a special category in the hierarchy of classification.
Linnaeus' invention of binomial nomenclature for designating species served systematic biology admirably, but at the same time, by attaching preponderating importance to a particular grade in classification, crystallized the doctrine of fixity.
The lower grades in classification such as sub-species and varieties on the one hand, and the higher grades on the other, such as genera and families, were admitted to be human conceptions imposed on the living world, but species were concrete, objective existences to be discovered and named.
Charles Darwin found the conception of species so definite and fixed that he chose for the title of his great book (1859) the words On the Origin of Species by Means of Natural Selection, although his exposition of evolution applied equally to every grade in classification.
The word "species" now signifies a grade or rank in classification assigned by systematists to an assemblage of organic forms which they judge to be more closely interrelated by common descent than they are related to forms judged to be outside the species, and of which the known individuals, if they differ amongst themselves, differ less markedly than they do from those outside the species, or, if differing markedly, are linked by intermediate forms. It is to be noted that the individuals may themselves be judged to fall into groups of minor rank, known as sub-species or local varieties, but such subordinate assemblages are elevated to specific rank, if they appear not to intergrade so as to form a linked.
of the periodic classification, along with the alkaline earth metals.
BERYLLIUM, or Glucinum (symbol Be, atomic weight 9.1), one of the metallic chemical elements, included in the same sub-group of the periodic classification as magnesium.
Table A following shows the classification of goods adoptec before the tariff revision of 1906.
From 1907 a new classificatior has been adopted, and the change thus introduced is so great that it is impossible to make any comparisons between th~ statistics of years subsequent to and preceding the year 1906 Table B shows imports and exports for 1907 and 1908 accordinf i to the new classification adopted.
Moreover, under the careful classification of affairs into local and central, many things which in England are regarded as local (e.g.
Forms. - Various schemes of classification have been proposed, but none has met with universal acceptance; the following are at least the principal types.
Rumanians These allotments were slightly modified at the polls by the victory of some Social Democratic candidates not susceptible of strict racial classification.
A classification of the groups in the new Chamber presents many difficulties, but the following statement is approximately accurate.
The plants, 626 in number, are enumerated alphabetically, but a system of classification differing little from Caspar Bauhin's is sketched at the end of the book; and the notes contain many curious references to other parts of natural history.
The first two editions of the Catalogus plantarum Angliae (1670, 1677) were likewise arranged alphabetically; but in the Synopsis stirpium Britannicarum (1690, 1696, also re-edited by Dillenius, 1724, and by Hill, 1760) Ray applied the scheme of classification which he had by that time elaborated in the Methodus and the Historia plantarum.
The greatest merit of this book is the use of the number of cotyledons as a basis of classification; though it must be remembered that the difference between the monocotyledonous and dicotyledonous embryo was detected by Nehemiah Grew.
At this time he based his classification, like Caesalpinus, chiefly upon the fruit, and he distinguished several natural groups,, such as the grasses, Labiatae, Umbelliferae and Papilionaceae.
The classification of the Methodus was extended and improved in the Historia plantarum, but was disfigured by a large class of Anomalae, to include forms that the other orders did not easily admit, and by the separation of the cereals from other grasses.
P. de Tournefort in taking the flower instead of the fruit as his basis of classification: he was no longer a fructicist but a corollist.
For accounts of Ray's system of classification, see Cuvier, Lecons hist.
"Classification" in Rees's Cyclopaedia.
But here, too, the preliminary classification of the documents is beset with doubt.
In the arrangement of the separate sections, a classification according to contents was impracticable because of the variety of subjects often dealt with in one sura.
Another division of the country is into Lower, Middle and Upper Egypt, Middle Egypt in this classification being the district between Cairo and Assiut.
The remains of Old Coptic, though very instructive in their marked peculiarities, are as yet too few for definite classification.
The forms observable in hieroglyphic writing lead to the following classification: STRONG VERBS.
This control was most often exercised by cancelling their classification as second-class matter entitled to low mailing rates.
g came to be employed in botanical classification as the name of a class, an arbitrary limitation had to be set to its signification, and this was not always in keeping with its original meaning.
It might be mentioned here that the whole group of the Fungi (q.v.),with its many thousands of species, is now generally regarded as having been derived from algae, and the system of classification of fungi devised by Brefeld is based upon this belief.
Further discussion of the general characters of algae will be deferred in order to take a brief survey of the subdivisions of the group. For this purpose there will be adopted the classification of algae into four sub-groups, founded on the nature the.
Brebner, " On the Classification of the Tilopteridaceae," Proc. Bristol Nat.
But American extinct types appear to indicate signs of intimate relationship between antelopes, prongbuck and deer, and it may be necessary eventually to amend the current classification.
This should be useful for establishing the date and classification of the earlier finds, which are in the British Museum.
He assisted Sir Wyville Thomson in the examination and classification of the collections of the "Challenger" exploring expedition, and wrote the Review of the Echini (2 vols., 1872-1874) in the reports.
will be found a classification of the holdings in 1895, 1903 and 1905.
Classification of this literature by traditional subdivision into genres is difficult, and, at the best, unprofitable.
Such evidence relates to the facts of classification, structure, development, and geographical and geological distribution.
The enforced adoption of new names makes it easy to lose the historical identity of many who really belonged to the Minster Anabaptists, and, on the other hand, has led to the classification of many with the Munster sect who had no real connexion with it.
His other principal works are: - Traite ele'mentaire de mneralogie, avec des applications aux arts (2 vols., Paris, 1807); Histoire naturelle des crustace's fossiles (Paris, 1822); Classification et caracteres mineralogiques des roches homogenes et hete'rogenes (Paris, 1827); the Tableau des terrains qui component l'ecorce du globe, ou Essai sur la structure de la partie connue de la Jerre (Paris, 1829); and the Traite des arts ceramiques (1844).
Oxygen is a member of the sixth group in the periodic classification, and consequently possesses a maximum valency of six.
In 1905 the iron and steel product had increased in value since 1900 44.9%, to $ 8 7,35 2, 7 61; the foundry and machine shop products 25.2%, to $79,9 61, 4 82; and the wire product showed even greater increase, largely because of a difference of classification in the two censuses, the value in 1905 being $14,099,566, as against $2,879,188 in 1900, showing an increase of nearly 390%.
In the medieval examinations described above we find most of the elements of our present examinations: certificates of previous study and good conduct, preparation of set-books, questioning on subjects not specially prepared, division of examinations into various parts, classification in order of merit, payment of fees, the presentation of a dissertation, and the defence and publication of a thesis (a term of which the meaning has now become extended).
The element of chance, which prevails in the region on either side of the border between pass and failure, obviously prevails equally on either side of the border between " classes," where candidates are classified; it has been suggested by Dr Schuster that numerical order should accompany classification so as to avoid the creation of an artificial gap between the last candidate in one class and the highest in the next.
To metamorphosis he only allowed a logical value, as explaining the natural classification; the only real, existent metamorphosis he saw in the development of the individual from its embryonic stage.
Corresponding to this division is the classification of the single arts.
As for the classification of sophistical methods, so for their criticism, the testimony of Plato is all-important.
He describes the classification of the people, dividing them, however, into seven castes instead of four, namely, philosophers, husbandmen, shepherds, artisans, soldiers, inspectors and the counsellors of the king.
He also studied the alkaloids and organic acids, introduced a classification of the metals according to the facility with which they or their sulphides are oxidized by steam at high temperatures, and effected a comparison of the chemical composition of atmospheric air from all parts of the world.
Ptolemy's classification has been adopted as the basis of the more exactly quantitative modern system.
The recognition of stars is primarily dependent on their brightness or " magnitude "; and it is clear that stars admit of classification on this basis.
Various schemes of classification of spectra have been used.
Sec±hi (1863-1867) who distinguished four " types "; subsequent research, whilst slightly modifying, has in the main confirmed this classification.