32 CHARACTERS OF COLEOPTER^E. 



parts of the tegumentary skeleton, and form two sheaths or solid 

 elytra, joined together by a straight edge, sometimes solidly 

 united, forming a kind of shield over the abdomen (figs. 23 and 

 26). Sometimes these elytra are rudimentary, but are never 

 entirely wanting in both sexes. The same is not true of the 

 wings of the second pair, which are membranous, much larger 

 than the elytra, and when in a state of repose, folded transversely 

 at their extremity ; sometimes they are wanting, and then the in- 

 sect is incapable of flying. There is no peculiarity of the legs 

 worthy of special remark. The abdomen is sessile, that is, it is 

 broadest where it joins the thorax, and on each side of the rings 

 which form it, there is, on the upper part, an opening, which is a 

 stigmata. 



9. The metamorphosis which the Coleop'teree undergo after es- 

 caping from the egg is complete. The larva resembles a soft 

 worm, the head of which as well as the three first rings of the 

 body are scaly (figs. 4, 9, 19, and 25). They generally have 

 three pairs of horny legs, terminating in a point. Sometimes 

 there are no legs, or they are replaced by small fleshy tubercles ; 

 but we never find a greater number of these appendages. The 

 mouth has the same organization as the perfect insect ; the eyes, 

 on the contrary, are merely represented by small granular bodies, 

 which seem to consist of an assemblage of simple eyes, which 

 never exist in adult Coleop'terae ; and we perceive on each side of 

 the body nine stigmata arranged in a series. 



10. The nympha is always inactive; sometimes it is enclosed 

 in a shell or cocoon, generally composed of different substances 

 joined together by a viscid, silky matter ; sometimes it is naked. 

 The duration of these changes and the mode of life, as well in 

 the larva as in the perfect insect, vary in the different families 

 of this order. 



11. The number of Coleop'terse is immense, and to distinguish 

 them more readily they are divided into four sections, according 

 to the number of articulations or joints of the tarsi ; namely, 



1st. The Pentame'rans (from the Greek, pente, five, and meros, 

 a joint), in which the tarsus of all the legs is composed of five 

 joints. 



2d. The Heterome'rans (from the Greek, 'eteros, various, and 

 xieros, joint), in which the tarsi have four articulations on the two 

 Tore legs, and five on the others. 



3d. The Teterame'rans (from the Greek, tetteres, four, and 

 meros, joint), in which the tarsi pf all the legs have four articula- 

 tions 



9. What description of metamorphosis do the Coleop'terse undergo ? 



10. What is the condition of the nymph of Coleop' terse ? 



11. How is the order of Coleop' tera divided ? 



