In most insects that feed by suction the mandibles are modified.
Biting mandibles; second maxillae completely fused.
Uzel, with the majority of students, regards the paired organs as mandibles and the unpaired as an epipharynx.
The actual piercing organs are the mandibles, while the upper lip or labrum forms a sucking tube.
The maxillae are not piercing organs, and their function is to protect the mandibles and labrum and separate the hairs or feathers of the host.
The head - carrying feelers, mandibles and two pairs of maxillae - is succeeded by the three thoracic segments, each bearing a pair of strong five-segmented legs, whose feet, like those of the adult, carry two claws.
Mandibles being well adapted for the capture of small insect-victims. The larvae are more specialized than those of other Adephaga, the head and prothorax being very large and broad, the succeeding segments slender and incompletely chitinized.
The noises made by some Ptinidae (Anobium) tapping on the walls of their burrows with their mandibles give rise to the "death tick" that has for long alarmed the superstitious.
The wings are well developed for flight, and there is a tendency in the group, especially among the males, towards an excessive development of the mandibles or the presence of enormous, horn-like processes on the head or pronotum.
The larvae are furnished with large heads, powerful mandibles and well-developed legs, but the body-segments are feebly chitinized, and the tail-end is swollen.
In the same species, however, great variation occurs in the development of the mandibles, and the breadth of the head varies correspondingly, the smallest type of male being but little different in appearance from the female.
The mandibles are strong, adapted for biting the vegetable substances on which these beetles feed, and the palps of the second maxillae have three segments.
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.
The mandibles, which are frequently used for carrying various objects, are situated well to the outside of the maxillae, so that they can be opened and shut without interfering with the latter.
These cocoons, which may often be seen carried between the mandibles of the workers, are the "ants' eggs" prized as food for fish and pheasants.
Sharp to hold the maggots between their mandibles and induce them to spin together the leaves of trees from which they form their shelters, as the adult ants have no silk-producing organs.
Accessory organs are rarely found on the genital ducts, but occur in Paludina, Cyclostoma, Naticidae, Calyptraeidae, &c. Mandibles usually present.
No mandibles, and radula uniserial.
The head of an insect carries usually four pairs of conspicuous appendages - feelers, mandibles and two pairs of maxillae, so that the presence of four primitive somites is immediately evident.
The mandibles often furnish a good example of "secondary sexual characters," being more strongly developed in the male than in the female of the same species.
As previously mentioned, a pair of minute jaws - the maxillulae- are present in the lowest order of insects, between the mandibles and the first maxillae.
In their typical state of development, the first maxillae offer a striking contrast to the mandibles, being composed of a two-segmented basal piece (cardo and stipes, fig.
2, IV) in which the slender piercers (mandibles and first maxillae) work to and fro.
In front or above the mouth is bounded by the labrum, while the mandibles and first maxillae lie on either side of it.
It has been shown by C. Janet (1889), from careful studies of the musculature, that the greater part of the head-capsule is built up of the four anterior head-segments, the hindmost of which has the mandibles for its appendages, and this conclusion is in the main supported by the recent work on the head skeleton of J.
- A remarkable feature in the embryonic segments of the mandibles and of the first and second maxillae.
Primitively (?) wingless Hexapods with cumacean mandibles, distinct maxillulae, and locomotor abdominal appendages.
Biting mandibles; minute but distinct - maxillulae; second maxillae incompletely fused.
Biting mandibles; vestigial maxillulae; second maxillae incompletely fused.
Biting mandibles; second maxillae incompletely fused.
Biting mandibles; second maxillae incompletely fused.
The second antennae, mandibles and two pairs of maxillae may also be claimed as of malacostracan type.
A, Female from above; d, Jaws, more highly magnified b, From beneath, magnified 5 (tips of mandibles and 1st times; maxillae still more highly c, Vestigial wing; magnified).
Fabre states that the lastnamed insect uses a stone for the temporary closing of her burrow, and the Peckhams have seen a female Ammophila take a stone between her mandibles and use it as a hammer for pounding down the earth over her finished nest.
Apart from this feature the Trichoptera also differ from the typical Neuroptera in the relatively simple, mostly longitudinal neuration of the wings, the absence or obsolescence of the mandibles and the semi-haustellate nature of the rest of the mouth-parts.
Through this temporary protection the active pupa, which closely resembles the mature insect, subsequently bites a way by means of its strong mandibles, and rising to the surface of the water casts the pupal integument and becomes sexually adult.
Snakes possess teeth in the maxillaries, mandibles, palatine and pterygoid bones, sometimes also in the intermaxillary; they may be absent in one or the ether of the bones mentioned.
Sharp, recurved teeth are carried by the mandibles, the pterygoids, palatines, maxillaries, and in the Pythoninae by the premaxillaries also.
The prefrontal bones are still in contact with the nasals as in the previous families, but the coronoid bones of the mandibles are absent as in the remaining families, and this loss also occurs in the Boine Charina.
The proboscis of tsetse-flies is without the paired piercing stilets (mandibles and maxillae) possessed by other bloodsucking Diptera, such as the female horse-flies and mosquitoes.
The segmentation of the prosoma and the form of the appendages bear a homoplastic similarity to the head, pro-, meso-, and meta-thorax of a Hexapod with mandibles, maxillary palps and three pairs of walking legs; while the opistho io i e d c b o a S' S" 2 I VT V S IV III II I Opisthosoma Prosoma FIG.
A minute entosternite having the above-described structure is found in the Crustacean Apus between the bases of the mandibles, and also in the Decapoda in a similar position, but in no Crustacean does it attain to any size or importance.