Page:Jardine Naturalist's library Entomology.djvu/84

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78
INTRODUCTION TO

sent remarks are of a more general nature, and applicable to the whole.

The majority of larvæ have a vermiform appearance, the body being long, narrow, and inclining to cylindric. Such as present this aspect are the kinds which differ most conspicuously from the perfect insect; the others differ only in parts which are not influential over the general appearance. An obvious division of larvæ, therefore, is into such as are wholly unlike the perfect insect, and such as bear a greater or less resemblance to it. They are all destitute of wings, and have the common character of being unfitted to propagate the species.

Some attempts have been made to classify larvæ in a manner similar to that followed with perfect insects. These have not, however, been attended with much success, both on account of the inherent difficulties of the subject, and our comparatively imperfect acquaintance with insects in that condition. Mr. MacLeay was the first who endeavoured to divide them into groups, to which he assigned names suggested by the analogy which they presented to other articulated animals. Thus, for example, he names Chilognathiform, such larvæ as offer certain analogical forms reminding us of scolopendræ; Chilopodiform, those resembling juli; and those resembling lepisma he terms Thysanouriform. This author applied his system to the larvæ of coleoptera only; Kirby and Spence adopted the idea and extended it to the other orders; and it has been more or less