The entomologist's text book : an introduction to the natural history, structure, physiology and classification of insects, including the Crustacea and Arachnida . resemble the perfect insect, but contracted, and as it weredestitute of life : they have limbs, it is true, which are sepa-rate from each other, but these limbs, as well as the entu*ebody, are covered with a membranous skin. This coveringexists in the other pupae, but is of a firmer consistence, imi-tating a kind of bark, and to which the term corticata maybe apphed, and more completely inclosing the limbs in onegeneral covering. To
The entomologist's text book : an introduction to the natural history, structure, physiology and classification of insects, including the Crustacea and Arachnida . resemble the perfect insect, but contracted, and as it weredestitute of life : they have limbs, it is true, which are sepa-rate from each other, but these limbs, as well as the entu*ebody, are covered with a membranous skin. This coveringexists in the other pupae, but is of a firmer consistence, imi-tating a kind of bark, and to which the term corticata maybe apphed, and more completely inclosing the limbs in onegeneral covering. To this kind of metamorphosis, whichLatreille considers as comprising the obtected and coarc-tate pupae, he has applied the term pupa obvoluta, ob-serving that the expression ohtecta applies to both, and thatthat of coarctata is too vague; but surely the structure ofthe dipterous coarctate pupa (i. e., an incomplete pupa in-closed in the skin of the larva) is much more analogous tothe structure of the true incomplete pupa of the bee andbeetle*, than it is to the obtected pupa of lepidopterous in-sects ; indeed, it appeals quite evident, that if the coarctate. Figs. 35, Larva—38, Pupa obtecta—37, Im^o of a butterfly {Hipparckia pamphilm). section must be sunk at all, it must be in favour of theincomplete, and not the obtected section. * In some species of beetles, the incomplete pupa is inclosed in theskin of the lar\a {Anthrenns, Chilocorus), thus being, in fact, realcoarctate pupae. 200 PTILOTA. The existence and the niimher of legs of the larva, thepermanent or variable form of the head, the comparativestructure of the organs of the mouth with those of theimago, the number of the spiracles and disposition of thetrachese, the moultings of the skin, and the quiescent oractive state of the pupa, are all important considerations,upon which the distribution of insects from the characters oftheir metamorphosis may be effected. Hence the Lepidoptera (figs. 35, 36, and 37), are dis
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Keywords: ., bookau, bookcentury1800, booksubjectcrustacea, booksubjectinsects
