By these nervures the wing is mapped out into a series of spaces of which one, the discoidal cell, is the most important.
The nervures have two functions, they support and strengthen the wing, and being hollow serve to convey nutritive fluid and afterwards air to the wing.
On the anterior margin the extended nervures make it rigid, while behind it is fine and flexible.
These nervures taper towards the extremity of the wing, and are strongest towards its root and anterior margin, where they supply the place of the arm in birds and bats.
Any small space, bounded by some part different in color or structure, as the spaces bounded by the nervures of the wings of insects, or those by the veins of leaves; an areola.
An interstice or small space, as between the cracks of the surface in certain crustaceous lichens; or as between the fibers composing organs or vessels that interlace; or as between the nervures of an insect's wing.
Their most distinctive characters are leaflets narrowed at the base, often lobed, and with nervures dividing in a pinnate manner from the base.
The leaflets are attached by the whole base, but not usually attached to each other; the midrib, though slender, attains to the summit; the nervures are given off less obliquely than in Neuropteris.
The midrib is continuous to the point, and the nervures run off from it nearly at right angles.
A genus established by Goeppert for a curious Pecopteris-like fern, with flexuous branching oblique nervures becoming parallel to the edge of the frond.
Their nervures are diverging rays, which issue either from a basal area or from the base itself, and terminate in the exterior margin[565].
They are however quite covered by irregular reticulations, produced by various nervures sent forth by the longitudinal ones, and running in all directions.
This membrane is surrounded by a strong and prominent nervure, and is concealed under the fold of the left elytrum, which has also several prominent nervures answering to the margin of the membrane or ocellus.
Thus the saw-flies have generally bodies thicker than those of most other Hymenoptera, while those that have fewer nervures are more slender.
It has been observed that the nervures of the wings are usually proportioned to the weight of the insect.
There is," he further remarks, "every reason to believe that the brisk movement with which the grasshopper rubs these nervures against each other, produces a vibration in the membrane augmenting the sound.
The nervures that traverse and extend them, though not numerous, are stronger and larger than those in the wings of insects of the other orders, and are so dispersed as to give perfect tension to the organ.
The vessels contained in the nervures consist of a spiral thread, whence they appear to be air-vessels communicating with the tracheae in the trunk.
Wings equally ample, forming the quadrant of a circle, and with five or six nervures diverging from their base, distinguish the strepsipterous tribe.
Its wings are orange-red, with black lines along the nervures and a row of white spots along the outer margins.
Defn: One of the ribs or nervures of the wings of insects.
Many grasshoppers stridulate by rubbing the hind legs across strong nervures on the fore wings.
Note: The crickets stridulate by rubbing together the strong nervures of the fore wings.
Defn: One of the principal nervures of the wings of an insect.
The term nervures, as applied to these markings, is not only misleading, but an incorrect use of one of Barrande's words, for by nervures he meant delicate surface markings.
In the Orthoptera and some Homopterous Hemiptera the nervures may be divided into longitudinal ones more or less ramified, and traversing ones.
In these the nervuresusually are few and dispersed, and seldom form any closed areolets.
In this Order the externo-medial and interno-medial nervures coalesce into one, and are only represented separately by their first and third branches[1894].
One of the ribs ornervures of the wings of insects.
From the rubbing of the belly against the network of nervures proceeds the species of puffing sound which I have compared to the hissing of an adder in a posture of defence.
The grating quality of the sound appears to be due to the little tongues which press on the nervures of the vibrating cymbals; the cause of its intensity is of course the ample resonator in the abdomen.
The rest of the wing-cover shows a few more nervures of less importance, which hold the membrane stretched tight, but do not form part of the friction apparatus.
I see other nervures in the intervals, pale and very fine.
The powerful nervures of the dorsal portion of the wing-cover are of the deepest black, and their general effect is that of a complicated design, not unlike a tangle of Arabic caligraphy.
The disposition of the radiating nervures, the skeleton of the structure, is not at all the same; the network formed by the cross-nervures gives no idea whatever of the complex final arrangement.
These tongues may be compared to the blade of a watchman's rattle, only instead of engaging with the teeth of a rotating wheel they touch the nervures of the vibrating cymbal.
I see a bundle of moderately strong nervures radiating fan-wise.
Its inner edge carries, on the under side, near the base, a callosity from which five radiating nervures proceed; two of them upwards and two downwards, while the fifth runs approximately at right angles to these.
A radiating bundle of strong nervures runs through it in the direction of its length and forms the framework of the fan, which is readily furled and unfurled.
Finally, still more delicate, and running transversely, a number of very short nervures complete the pattern.
The wings are heavy, moist, transparent, with nervures of a tender green.
The intervals are crossed by innumerable cross-nervures of slighter substance, which make of the whole a network of rectangular meshes.
The left or lower wing-cover is of similar structure, with the difference that the bow, the callosity, and the nervures occupy the upper face.
In the Pieridae there are two anal nervures in the hindwing, while the second anal nervure in the forewing runs into the first; the larva is cylindrical and hairy without an osmaterium.
Two or more of the radial nervures in the forewing arise from a common stalk or are suppressed.
But the Noctuides differ from these groups in having only two anal nervures in the hindwing.
Three anal nervures are present in the hindwing in those families whose wings are well developed, but in several families of small moths the wings of both pairs are very narrow and pointed, and the neuration is consequently reduced.
The forewing has only three or four radial nervures (fig.
Entrance for a pin-point between them is to be found at the base of the wing where the subcostal and median nervures come close together.
At that time the nervures are in two parts, half in one membrane and half in the other, and open in the centre.
Smith, which Ducke considers a synonym of laeta, but the base of the metathorax seems to differ, and the nervures are piceous.
One of the nervures (a) on the under surface of the former is finely serrated, and is scraped across the prominent nervures on the upper surface of the opposite or right wing.
The wing, when not in use, is folded both lengthwise and transversely, and doubled up beneath the elytron; to permit the transverse folding, the longitudinal nervures are interrupted.
There are several curved median and cubital nervures and a single anal, but few crossnervures or areolets.
Close to a transverse fold near the base of the wing, the median nervure divides into branches which extend to the wing-margin; there is a second transverse fold near the tip of the wing, and cross nervures are altogether wanting.
The very foliage is princely; for the nervures and cross-veins form a network pattern of dark green upon the light green area of each broad leaf.
The methodical classifier, who works in cemeteries and seems to fly the living cities, keeps the two families far removed from each other because of considerations and attaching to the nervures of the wings and the joints of the palpi.
In the dragon-flies, the nervures are minutely netted for the sake of increased strength; in the bees, the nervures are simply parallel.
These air-tubes, it will be remembered, are lined by spires of dense cartilage; and hence it is that they become nervures so well adapted to act like tent-lines in keeping the expanded membranes stretched.
Chabrier, a French entomologist, having observed a fluid in the interior of the nervures of the wings of insects, thinks it probable that they can introduce it into them and withdraw it at their pleasure, so as to facilitate their unfolding.
If you clip the wings of a butterfly during the process of expansion, you will see that the nervures are not only hollow, but that, however dry and empty they may subsequently be found, they at that time actually contain such a fluid.
The above list will hopefully give you a few useful examples demonstrating the appropriate usage of "nervures" in a variety of sentences. We hope that you will now be able to make sentences using this word.
