Alternate or opposite leaves, often with membranous united stipules.
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.
A membranous, or ossified, tube which rises from a pneumatic foramen in the os articulare, on the median side of the articulation, and passes upwards between the quadrate and lateral occipital bone, opening into the cavity of the middle ear.
In birds, this stalk consists entirely of blood-vessels, which in the adult enclose no terminal vesicle, and fuse with the membranous linings of the skull.
3.) The middle ear communicates with the mouth by the Eustachian tubes, which pass between the basisphenoid and basioccipital bones, and unite upon the ventral side of the sphenoid, a little behind its articulation with the pterygoids, where they open into the mouth cavity by a short membranous duct.
The interauricular septum is mostly entirely membranous; in the middle it is thinner, rather transparent, but there is no depression or fossa ovalis.
Tower (1903), of nervures similar to those of the hind-wing, and by the proof that the small membranous structures present beneath the elytra of certain beetles, believed by Meinert to represent the whole of the true fore-wings, are in reality only the alulae.
The chief characteristic of the Diptera is expressed in the name of the Order, since, with the exception of certain aberrant and apterous forms, flies possess but a single pair of membranous wings, which are attached to the meso-thorax.
Membranous, net-veined wings, those of the two pairs closely alike.
The bark in most of the trees occurs in fine soft membranous layers, the outer cuticle of which peels off in thin, white, papery sheets.
Two or three membranous flaps, held by numerous chordae tendineae, form a true mitral valve, and allow the blood to pass through the left ostium atrioventriculare.
The insects of this order have mandibles adapted for biting, and two pairs of membranous wings are usually present; the first abdominal segment (propodeum) becomes closely associated with the fore-body (thorax), of which it appears to form a part.
Cephalic shield ending posteriorly in a median point; shell internal, largely membranous; no radula or stomachal plates.
Cephalic shield pointed behind; shell internal, chiefly membranous, with calcified nucleus, nautiloid; parapodia forming fins.
Dorsal papillae with a membranous expansion; male and female apertures at some distance from each other; pelagic. Fiona.
The regions of this cuticle have a markedly segmental arrangement, and the definite hardened pieces (sclerites) of the exoskeleton are in close contact with one another along linear sutures, or are united by regions of the cuticle which are less chitinous and more membranous, so as to permit freedom of movement.
The head is usually connected with the thorax by a distinct membranous neck, strengthened in the more generalized orders with small chitinous plates (cervical sclerites).
Fore-wings modified into firm elytra, beneath which the membranous hind-wings (when present) can be folded.
Two pairs of similar, membranous wings, with predominantly longitudinal neuration.
Two pairs of membranous, hair-covered wings, with predominantly longitudinal neuration.
Wings membranous, fore-wings larger than hind-wings.
Of special interest are cockroachlike forms, with two pairs of similar membranous wings and a long ovipositor, and gigantic insects allied to the Odonata, that measured 2 ft.
The spinning appendages migrate to the posterior end of the opisthosoma and take up a position close to the anus; the inner branches of the anterior pair either atrophy or are represented homogenetically by a plate, the cribellum, or by an undivided membranous lobe, the colulus.
Appendages of 2nd pair very large and completely chelate, their basal segments meeting in the middle line, as in the Uropygi, and provided in front with membranous lip-like processes underlying the proboscis.
A movable membranous j oint between the prosoma and the opisthosoma, the generative aperture opening upon the ventral side of the membrane.
AaK6s, a bag), a botanical term for the membranous sacs containing the reproductive spores in certain lichens and fungi.
A small group of Australian genera closely approach the order Juncaceae in having small crowded flowers with a scarious or membranous perianth; they include Xanthorrhoea (grass-tree or blackboy) and Kingia, arborescent plants with an erect woody stem crowned with a tuft of long stiff narrow leaves, from the centre of which rises a tall dense flower spike or a number of stalked flower-heads; this group has been included in Juncaceae, from which it is doubtfully distinguished only by the absence of the long twisted stigmas which characterize the true rushes.
Leaves which are grass-like or cylindrical or reduced to membranous sheaths.
The flowers are hermaphrodite and regular, with the same number and arrangement of parts as in the order Liliaceae, from which they differ in the inconspicuous membranous character of the perianth, the absence of honey or smell, and the brushlike stigmas with long papillae-adaptations to wind-pollination as contrasted with the methods of pollination by insect agency, which characterize the Liliaceae.
Many other diseases formerly regarded as primarily diseases of the nervous system are not such; but, by means of agents either introduced into the body or modified there, establish themselves after the affinities of these in contiguous associated parts of the structure, as in vascular, membranous or connective elements, or again in distant and peripheral parts; the perturbations of nervous function being secondary and consequential.
The hind wings, on the contrary, are for the most part membranous and, when extended, of large size; each consists of two portions, the distal of which, in virtue of the arrangement and jointing of its nervures, is capable of being both doubled up and folded fanwise beneath the proximal, which is partly horny when the wing is tucked away under the front wing-case of the same side.
The seeds are provided with a long membranous wing.
Body - wall membranous or calcified, body cavity distinct.
- Zooecia with soft uncalci fled' walls, the external part of the introvert being closed during retraction by a membranous collar.
The free (frontal) wall may remain membranous and uncalcified, or as in Membranipora (figs.
The evolution of the arrangements for protruding the polypide seems to have proceeded along several distinct lines: (i.) In certain species of Membranipora the "frontal membrane," or membranous free-wall, is protected by a series of calcareous spines, which start from its periphery and arch inwards.
The arrangement is perhaps derivable from a Cribrilina-like condition in which the outer layer of the spines has become membranous while the spines themselves are laterally united from the first.
The plants have long narrow leaves springing from the bulb and a central scape bearing one or more generally large, white or yellow, drooping or inclined flowers, which are enveloped before opening in a membranous spathe.
Both foreand hindwings are usually present, both pairs being membranous, the hindwings small and not folded when at rest, each provided along the costa with a row of curved hooks which catch on to a fold along the dorsum of the adjacent fore-wing during flight.
The name was first used by Linnaeus (1735), who derived it from the half-coriaceous and half-membranous condition of the forewing in many members of the order.
The fore-wings are sometimes membranous like the hind-wings, usually they are firmer in texture, but they never show the distinct areas that characterize the wings of Heteroptera.
The pair of renal organs of Anodonta, called in Lamellibranchs the organs of Bojanus, lie below the membranous floor of the pericardium, and open into it by two well-marked apertures (e and f in fig.
The tenth abdominal segment carries a pair of jointed cerci which are often elongate, and the feelers are always long, while the jaws are usually feeble and membranous, though the typical parts of a mandibulate mouth are present - mandibles, maxillae with inner and outer lobes and palps, and second maxillae (labium) whose lacinae are not fused to form a ligula.
Structurally the Neuroptera are distinguished by elongate feelers, a large, free prothorax, a labium with the inner lobes of the second maxillae fused together to form a median ligula, membranous, net-veined wings without hairy covering, those of the two pairs being usually alike, the absence of abdominal cerci, and the presence of six or eight Malpighian tubes.
The male urethra begins at the bladder and runs through the prostate and perineum to the penis, which it traverses as far as the tip. It is divided into a prostatic, membranous and spongy part, and is altogether about 8 inches in length.
Near the lower part of the verumontanum is a little pouch, the utriculus masculinus, about one-eighth of an inch deep, the opening of which is guarded by a delicate membranous circular fold, the male hymen.
Opening into the spongy urethra where it passes through the bulb are the ducts of two small glands known as Cowper's glands, which lie on each side of the membranous urethra and are best seen in childhood.
This is known as the membranous urethra, and is very narrow, being gripped by the compressor urethrae muscle.
The bulb, which is the only part eaten, has membranous scales, in the axils of which are io or 12 cloves, or snialler bulbs.
Within the glottis is a pair of membranous folds which serve as vocal cords; all the Crocodilia are possessed of a loud, bellowing voice.
B, b', Upper and lower membranous spathe-like bracts; c, Tube of perianth; d, Ovary; e, Style; f, Stigmas.
The membranous spathes have been cut and drawn aside, revealing the spike of fruit which bears the long silky styles.
7rLru), a name given by the ancients to some of the resinous cone-bearing trees to which it is now applied, and, as limited by modern botanists, the designation of a large genus of true conifers, differing from the firs in their hard woody cone-scales being thickened at the apex, and in their slender needle - shaped leaves growing from a membranous sheath, either in pairs or from three to five together - each tuft representing an abortive branch, springing from the axil of a partially deciduous scale-leaf, the base of which remains closely adherent to the stem.
The same purpose is probably served by the extreme flattening of the body in the membranous Phyllosoma-larva of the rock-lobsters and their allies (Loricata).
The only facts in natural history which appear even indirectly to countenance the flotation theory are the presence of a swimming bladder in some fishes, and the existence of membranous expansions or pseudowings in certain animals, such as the flying fish, flying dragon and flying squirrel.
The diseases to which the act applies are smallpox, cholera, membranous croup, erysipelas, scarlatina or scarlet fever, typhus, typhoid, enteric, relapsing, continued or puerperal fever, and any other infectious disease to which the act has been applied by the local authority of the district in the prescribed manner.
2) consists of a receptacle varying in form from that of a shallow saucer to that of a long cylindrical or trumpet-shaped tube, thin or fleshy in consistence, and giving off from its upper border the five sepals, the five petals (rarely these latter are absent), and the threads or membranous processes constituting the "corona."
It is of thin membranous consistence, usually obtuse, often bifid, and possesses no central rib or nerve, but has two lateral ones, one on either side; the margins are frequently folded in at the ribs, which thus become placed at the sharp angles.
Sometimes the pericarp is membranous, sometimes hard, forming a nut, as in some genera of Bambuseae, while in other Bambuseae it becomes thick and fleshy, forming a berry often as large as an apple.
The testa is thin and membranous but occasionally coloured, and the embryo small, the great bulk of the seed being occupied by the hard farinaceous endosperm (albumen) on which the nutritive value of the grain depends.
Part of the membranous roof between the supra-occipital and parietal bones frequently remains unossified and presents in the macerated skull a pair of fontanelles.
At the summit of l i the sheath, above the origin of the blade, is the ligule, a usually membranous process of small size (occasionally reaching r in.