Hexapoda mostly with wings, the wingless forms clearly degraded.
Fleas are wingless insects, with a laterally compressed body, small and indistinctly separated head, and short thick antennae situated in cavities somewhat behind and above the simple eyes, which are always minute and sometimes absent.
Starting with the kiwi and cassowary, people have got into the habit of confounding flightless with wingless conditions.
In the wingless female glow-worm (Lampyris, fig.
Spicuous and well-known feature of ants is the wingless condition of the " workers," as the specialized females, with undeveloped ovaries, which form the largest proportion of the population of ant-communities, are called.
Such " workers " are essential to the formation of a social community of Hymenoptera, and their wingless condition among the ants shows that their specialization has been carried further in this family than among the wasps and bees.
The winter moth (Cheimatobia brumata) must be kept in check by putting greasy bands round the trunks from October till December or January, to catch the wingless females that crawl up and deposit their eggs in the cracks and crevices in the bark.
- The Hop Aphis (Phorodon After the Coccidae the next most important insects male; C, ovigerous wingless female; economically are r the plant lice or A phididae.
A, Winged female; B, winged D, viviparous wingless female from in patches from old apple trees, where the insects live in the rough bark and form cankered growths both above and below ground.
Large pits are dug across the line of advance of these great insect armies to stop them when in the larval or wingless stage, and even huge bonfires are lighted to check their flight when adult.
The wings of insects are, in all cases, developed after hatching, the younger stages being wingless, and often unlike the parent in other respects.
Rarely the male is the wingless sex.
These two endoderm-rudiments embryonic membrane formed by delamination from the blastoderm, ultimately grow together and give rise to the epithelium of the midwhile in a few insects, including the wingless spring-tails, the emgut.
Wingless insects, such as spring-tails and lice, make their appearance in the form of miniature adults.
His order of wingless insects (Aptera) included Crustacea, spiders, centipedes and other creatures that now form classes of the Arthropoda distinct from the Hexapoda; it also included Hexapoda of parasitic and evidently degraded structure, that are now regarded as allied more or less closely to various winged insects.
Consequently the modern order Aptera comprises only a very small proportion of Linnaeus's " Aptera " - the spring-tails and bristle-tails, wingless Hexapoda that stand evidently at a lower grade of development than the bulk of the class.
Sharp's proposed association of the parasitic wingless insects in a group Anapterygota cannot, however, be defended as natural; and recent researches into the structure of these forms enables us to associate them confidently with related winged orders.
Primitively (?) wingless Hexapods with cumacean mandibles, distinct maxillulae, and locomotor abdominal appendages.
Mallophaga: Parasitic wingless Corrodentia (Bird-lice).
Wingless, parasitic forms. Cerci absent.
Hexapoda mostly with wings; the wingless forms clearly degraded or modified.
Many students of the group, following Brauer, have regarded the Apterygota as representing the original wingless progenitors of the Pterygota, and the many primitive characters shown by the former group lend support to this view.
It is most unlikely that wings have been acquired independently by various orders of Hexapoda, and if we regard the Thysanura as the slightly modified representatives of a primitively wingless stock, we must postulate the acquisition of wings by some early offshoot of that stock, an offshoot whence the whole group of the Pterygota took its rise.
The wingless forms in question are always allied to winged forms, and there is every reason to believe that they have been really derived from winged forms. There are also insects (fleas, &c.) in which metamorphosis of a " complete " character exists, though the insects never develop wings.
These cases render it highly probable that insects may in some circumstances become wingless, though their ancestors were winged.
There are, in fact, existing forms of Exopterygota that are usually wingless, and that nevertheless appear in certain seasons or localities with wings.
Lus), a term applied to small wingless insects, parasitic upon birds and mammals, and belonging strictly speaking to the order Anoplura, often included among the Hemiptera, though the term is frequently extended to the bird-lice constituting the suborder Mallophaga, formerly included among the Neuroptera.
The kagu (Rhinochetus jubatus), a peculiar "wingless" bird, is found here only.
The larvae are perfectly white at first and wingless, although in other respects not unlike their parents, but they are not mature insects until after the sixth casting of the skin.
Wingless females of many tropical species present a close superficial resemblance to woodlice; and one interesting apterous form known as Pseudoglomeris, from the East Indies, is able to roll up like a millipede.
It is only necessary here to mention one anomalous form, Enoicyla pusilla, in which the mature female is wingless and the larva is terrestrial, living in moss or decayed leaves.
Many species are wingless at all ages.
The females are always wingless, but are provided with antennae, legs and well-developed mouth-parts.
It has roundish cones, with numerous scales and wingless seeds.
All the known forms of plant-life are either fungi or allied to them, and many are only microscopic. The most interesting inhabitants of Mammoth Cave are the blind, wingless grasshoppers, with extremely long antennae; blind, colourless crayfish (Cambarus pellucidus, Telk.); and the blind fish, Amblyopsis spelaeus, colourless and viviparous, from 1 in.
APTERA (Greek for "wingless"), a term in zoological classification applied by Linnaeus to various groups of wingless arthropods, including some of the insects, the centipedes, the millipedes, the Arachnida (scorpions, spiders, &c.) and the Crustacea.
Many wingless insects - such as lice, fleas and certain earwigs and cockroaches - are placed in various orders together with winged insects to which they show evident relationships.
But the bristle-tails and springtails, which form the modern order Aptera, are all without any trace of wings, and, on account of several remarkable archaic characters which they exhibit, there is reason for believing that they are primitively wingless - that they represent an early offshoot which sprang from the ancestral stock of the Hexapoda before organs of flight had been acquired by the class.
Those of the highest zone are remarkable for the great predominance of predaceous species and of wingless forms. In this last respect they present a striking analogy with the endemic coleopterous fauna of oceanic islands.
The Hemimeridae include the single genus Hemimerus, which contains only two species of curious wingless insects with long, jointed cerci, found among the hair of certain West African rodents.
Wingless forms are fairly frequent in the order, but their relationship to the allied winged species is evident.
Some Embiidae are entirely wingless in the adult state, and it has been suggested that this is always the condition in the female sex.