542 



ARTICULATA. 



more or U-ss s|.lRTu-al Ibrin, soinctiiiKs oval or kidney-shaped, and in a few cases divided into 

 two parts by an elevated ridge, so that tlie insect appears to have four eyes; while in a few 

 beetles, irdiai>iting caves or other subterranean situations, the eyes are entirely wanting. 



The thoracic se<rments are ahvavs distinctly separated. The prothorax is usually of consider- 



able size, and boars tho first pair of legs. 



f' r- 



'^^^ .^ 



HERCULES BEETLE. 



The mesothorax and inetathorax boar the other two 



pairs of legs and the elytra and 

 wdngs, beneath which their up- 

 per surface is entirely concealed, 

 with the exception of a sinal) 

 triangular piece of the meso- 

 thorax — the sciitellum — which 

 is usually visible at the base of 

 the suture. The elytra gener- 

 ally cover the entire dorsal sur- 

 face of the body to the apex of 

 the abdomen, and the upper 

 portion of these segments is 

 then of a soft and somewhat 

 membraneous texture ; but in 

 some cases the elytra are short, 

 leaving a greater or less portion 

 of the abdomen uncovered ; 

 this is then equally homy on 

 both surfaces. In some cases 

 the wings are wanting, when 

 the elytra are not unfi'equently 

 completely soldered together. 

 The legs are usually constructed exclusively for walking ; but in some cases the fore-legs are con- 

 verted into fossorial organs, and in others the hind-logs are flattened for swimming, or furnished 

 with thickened thighs for saltatorial purposes. The tarsi are generally composed of five joints, 

 and this appears to be the normal number. The number varies, however, in diflferent groups 

 from two to five. 



The metamorphosis of the Coleoptera is complete ; the larva is usually a soft fleshy grub, 

 although the texture of its integuments is often leathery, or even somewhat horny, especially in 

 the rapacious species. The soft larva; are almost alwaj^s furnished with a horny head, armed 

 with distinct jaws, and usually furnished with simple eyes. They are generally furnished Avith 

 six thoracic legs, although these are sometimes wanting, and frequently also with anal pro-legs. 

 The pupaj are free and quiescent. 



"We shall notice the insects of this order under the following subdivisions: the Pentamera, 

 the ffetcromcra, Tetratnera, and Trimera. 



THE PENTAMERA. 



This term, derived from the Qxeok pente, five, and mera, divisions, is applied to the insects of 

 this group, as most of the species have their tarsi composed of five distinct joints; they are, 

 however, very numerous, and there are great variations in structure. 



THE GEODEPHAGA. 



Tliis term signifies Ground-Beetles^ and is descriptive of the tribe. They are exceedingly 

 active, and often beautiful insects ; generally nocturnal in their habits, concealing themselves 

 during the day under stones and in holes in the ground. The larvae are elongated, flattened, and ' 

 usually covered with a horny integument. In their predaceous habits they resemble the perfect , 

 insects. } 



The insects of one family, the Cicindelidce, which have received the name of Tiger-Beetles, 



