492 



INSECTA. 



The first section comprises the Pentamera, or those which have five joints in all the tarsi, 

 and which consist of six families, of which the first two are distinguished by the possession of 

 a doable excretnentitial apparatus.* 



THE FIRST FAMILY OF THE COLEOPTERA PENTAMERA — 

 Carnivora, Cuv. (Adephaga, Clair.), — f 



Which has two palpi to each maxilla, or six in the whole. The antennae are almost always thread- 

 like or setaceous, and simple. The maxillae are terminated hy a scaly piece or slender hook ; and the 

 inner edge is furnished with hairs or small spines. The tonguelet is received in a notch of the 

 mentum. The two fore-legs are inserted upon the sides of a compressed sternum, hy means of a 

 large rotule ; the posterior pair have a strong trochanter at the base ; their basal joint is large, and 

 fippears to be soldered with the post-sternum, in the form of a curvilinear triangle, with the outer 

 edge excavated. 



These insects hunt after and devour other insects ; many have no wings under the elytra. The 

 anterior tarsi in many of the males are dilated. 



Their larvae are also very carnivorous. They have, in general, the body cylindric, elongated, and 

 composed of twelve joints ; the head (not counted in this number) is large, scaly, armed with two 

 strong mandibles bent upwards at the point, with two short conical antennae, two maxillae, divided into 

 two branches, of which one is formed by the palpus ; a tonguelet, bearing two short palpi ; and six 

 small smooth eyes on each side. The first segment is eovered by a scaly plate : the others are softer. 

 Each of the anterior segments bears a pair of feet, of which the extremity is curved in front. These 

 larvae differ according to the genera. Those of the Cicindelae, and Aristus bucephalus, have the upper 

 side of the head deeply impressed in the middle, with its under side very globose. They have on each 

 side two of the small smooth eyes much larger than the rest. The upper plate of the fore segment is 

 large, and like a semicircular shield. The eighth segment has upon the back two hooked tubercles. 

 The last segment has no particular appendages. 



In the other larvae of this family with which we are acquainted, with the exception of Omophron, 

 the head is not so strong and regular on its upper side. The ocelli are very small, and all alike. 

 The scaly back of the first segment is square, and does not extend beyond the side of the body. The 

 eighth segment is destitute of tubercles, and the last is terminated by two conical appendages, as well 

 as a membranous tube, formed of the elongation of the anal apparatus. These conical appendages are 

 corneous and toothed in the larvae of Calosoma and Carabus : they are fleshy, articulated, and longer in 

 the Harpali and Licini. The form of the mandibles approaches that of the perfect Beetles. The larvae 

 of Omophron limbatus, according to Desmarest, is of a conical form, with a large head, and two very 

 strong mandibles, and with only two eyes : the extremity of its body, which is gradually narrowed, is 

 terminated by an appendage of four joints. I have only counted two in those of the larvae of the 

 Licini and Harpali. 



These insects are either terrestrial or aquatic. 



The terrestrial Carnivora have the legs fit only for running ; the four posterior are inserted at 

 equal distances apart : the mandibles are entirely exposed ; the terminal piece of the maxillae straight 

 beneath, and bent only at the tip ; the body generally oblong, with the eyes prominent. All the 

 tracheae are tubular or elastic. The intestine is furnished with two small sacs, which secrete an acrid 

 humour. M. L. Dufour has presented (in the Annales des Sciences Naturelles, vol. viii. p. 36,) a 

 resume of the anatomical characters of these insects, [from which it appears that the digestive tube is 

 not more than twice the length of the body ; the gizzard is armed interiorly with moveable corneous 



the forms of their larvee ; he has, however, only given a slight sketch, 

 which recent discoveries do not seem to support. Mr. Kirby has 

 also proposed another arrangement in the Fauna Borealis Americana, 

 founded exclusively upon the general structure of the perfect insect.] 

 • Linnxus, Fabricius, and their followers commence the arrange- 

 ment of the Beetles witli the genus Scarabacus : which comprises 

 gome of the most bulky of the insect tribes, as, for instance, the Rhi- 

 noceros, Elephant, and Goliath Beetles. The arrangement of Latreille 

 is founded upon the supposed superior developement of the masti- 



catory organs of the Adephaga, and especially upon the circumstance 

 of their possessing two pairs of palpi to each of the maxilla;. Mr. 

 Hope, in the preface to the second part of his Coleopterist's Manual, 

 has supported the Linnaean arrangement with various arguments.] 



t This family, one of the most extensive of the insect tribes, has 

 been illustrated by Weber, Clairville, Bonelli, and especially by Dejean 

 in his Species Genera'., [now completed by himself, as regards the land 

 Carnivora, and continued by Dr. Aube, as regards the aquatic speriedj. 



