COLEOPTERA. 339 



besides, undergo true metamorphoses, analogous to those of several Diptera, 

 such as the Tipulae. 



This order consists of a single genus, that of 



PULEX, Linneeus. 



The body of the Flea is oval, compressed, invested by a firm skin, and 

 divided into twelve segments, three of which compose the trunk, that is short, 

 and the others the abdomen. The head is small, strongly compressed, 

 rounded above, and truncated and ciliated before; it is furnished on each side 

 with a small rounded eye, behind which is a fossula, in which we discover a 

 little moveable body furnished with small spines. The legs are strong, the 

 last ones particularly, fitted for leaping, and spinous ; the coxa and femur are 

 large; the tarsi is composed of five joints, the last terminating in two 

 elongated hooks ; the two anterior'legs are inserted almost under the head, the 

 rostrum being placed midway between them. 



The female lays a dozen of white and slightly viscid eggs ; the larvae have 

 no feet, are much elongated, resemble little worms, and are extremely lively, 

 rolling themselves into a circle or spirally, and crawl with a serpentine 

 motion ; they are first white and then reddish. Their body is composed of a 

 scaly head, without eyes, bearing two very small antennae ; and of thirteen 

 segments, with little tufts of hairs, the last one terminated by two kinds of 

 hooks. Some small moveable pieces are observed in the mouth, by which these 

 larvae push themselves forwards. After remaining twelve days under this 

 form, they enclose themselves in a little silky cocoon, in which they become 

 pupae, and from which, in about the same time, they issue in their perfect 

 state. 



These are various species that live on quadrupeds, birds, &c. 



ORDER V. 



COLEOPTERA. 



COLEOPTEROUS insects have four wings, the two superior of which resemble 

 horizontal scales, joining in a straight line along 

 the inner margin ; the inferior wings are merely 

 folded transversely and covered with others, which 

 form cases or covers for them, usually denominated 

 the elytra. 



Of all insects, these are the most numerous and 

 the best known. The singular form and brilliant 

 colouring of many species, the volume of their 

 bodies, the greater solidity of their teguments, which 

 facilitates their preservation, the numerous advan- 

 z 2 



