22 



L A M E L L I C O R N K S. 



for biting,and other partsof the mouth and two antennae. 

 The body is composed of twelve rings, of which the 

 hist is the largest, and to the first three of which six 

 sral v legs are attached ; each side the body is fur- 

 nished with nine spiracles ; the extremity of the body 

 is rounded and generally curved towards the breast, 

 so that the back being convex or arched, the larvae 

 cannot, conveniently stretch themselves in a straight 

 direction ; they consequently crawl but badly, con- 

 stantly tumbling to one side or the other ; but the legs 

 of these larva; arc not walking legs, neither do their 

 habits and localities require any such powers ; so that 

 the apparently awkward form of the body is seen, 

 when these are taken into consideration, to be not so 

 unnatural as was at first supposed. They feed upon 

 dung, manure, rotting bark, the roots of vegetables, 

 &c.. so that being in the midst of their food, powerful 

 locomotive organs would be useless. Still legs are 

 needed in order to enable the larvae to make their 

 way through the food. An idea may be obtained of 

 the general form of these grubs from the figure of the 

 preparatory stages of Cetonia, given in the article 

 CETONIID^E, or that of the larva of Trichius, figured 

 in the article INSECT ; sometimes, as is the case with 

 the larva of the cockchaffer, considerable damage is 

 produced by their ravages. In some species the 

 larva state extends for three or four years, at the ex- 

 piration of which they form, in their retreats, an oval 

 or elongate cocoon, composed of earth or the remains 

 of the materials which they have devoured, and which 

 they agglomerate together with a secretion which 

 they emit for that purpose. 



The nervous system of these insects, as considered 

 in the larva and imago states, is subject to very re- 

 markable variations, the ganglions being less nume- 

 rous, or rather the greater number being confluent in 

 the perfect state ; the two posterior emitting a great 

 number of elongated filaments, disposed like rays. 

 The digestive system, as in all herbivorous insects, is 

 considerably elongated. 



In the new edition of Dejean's Catalogue, we find 

 2060 species of lamellicorn insects noticed ; of this 

 number, scarcely more than a twentieth part occur in 

 this country, and of these the majority are of small 

 size ; but in our native list are to be mentioned the 

 cockchaffer and stag-beetle, two of our largest coleo- 

 pterous insects. But those are comparatively of 

 email size, when placed in contrast with some of the 

 exotic species. This group of insects has formed the 

 subject of a most elaborate treatise by Mr. MacLeay, 

 forming a portion of the Horae Entomologicae, by whom 

 the intimate relation of the HisteridtE with the Luca- 

 nid<e (Recticera, Thalerophaga, MacLeay) was proved, 

 and by whom the Petalocera, or that portion of the 

 lamellicorn beetles corresponding with the Linnaean 

 genus ScaralxEus, was divided and arranged as follows. 



Petalocera. 



By this diagram, which in some degree illustrates 

 the quinarian views and theory of Mr. Mat-Leay, it 

 will be seen that the Petalocera are divisible into two 

 groups, named Thalerophaga and Saprophaga, from 

 the difference in their haliits, the former feeding upon 

 leaves and the latter upon moist decaying vegetable 

 matter; that each of these two groups is divisible 

 into five families ; that these five families are allied 

 together in such manner that they form a circle ; 

 and that the opposite families in each circle oH'er 

 certain resemblances of analogy not only from the 

 general form of the species, but also from the struc- 

 ture of the mouth, and consequently in the manner 

 of living. 



The following are the characters of the ten families 

 into which Mr. MacLeay divides the Linnaean Sca- 

 rabtei, with their corresponding groups according to 

 Latreille. We shall defer our observations upon the 

 lucanideous portion of the LameUicornes, until we 

 arrive at the article LUCANUS. 



PETALOCERA, Dumeril ; SCARAB^US, Linnaeus ; 

 antenna? not elbowed, with a lamellate club ; mandi- 

 bles generally concealed. 



A. Sftyrop/taga. Leas strong, the posterior pair 



remote, tibiae broad, elytra often coyering 



the anus. 



* Coprophagi, dung feeders ; maxillae with mem- 

 branous lobes, and therefore living upon juices, and 

 as it were by licking their food. 



1. Gcotrujiidts, MacLeay (Arcnicoles gcolrttpi- 



dcs, Latreille); mandibles corneous por- 

 rected ; feed upon moist excrement ; 

 reside under dung or in boleti ; digging 

 under ground. 



2. ScarabizidcE, MacLeay (Coprophagi srarn- 



bceides, p. Latreille); mandibles membran- 

 ous, concealed under the clypeus, palpi 

 hairy with the last joint small ; feed upon 

 moist excrement ; reside in dung ; fly in 

 the twilight. 



3. Apkodiidee, MacLeay (Coprophagi scara- 



baiides, p. Latreille) ; mandibles membran- 

 ous, concealed, palpi naked with equal 

 sized joints; feed upon moist excrement ; 

 reside in dung ; fly in the sunshine. 

 ** Xerophaga, feeders upon rotten vegetable mat- 

 ter ; maxilla? horny, and therefore live on a more 

 solid species of food, and by mastication. 



4. Trogidae, MacLeay (Arcnicoles trogides, La- 



treille) ; muxillae with two lobes, and a 

 corneous curved tooth, anus covered ; live 

 in sandy places ; feed on putrid matters. 



5. DynastultE, MacLeay (Xyloj)hili, p. La- 



treille) ; maxillae dentate or unarmed, with 

 one lobe, anus naked ; feed on wood ; 

 reside in rotten wood, or under bark. 



B. Thalerophaga, legs more slender, tibiae narrower, 



elytra seldom covering the anus. 

 * Phyllophaga, leaf-eaters ; maxilloe corneous. 



t>. Anoplognathidte. MacLeay (1'hyllophagi, p. 

 Latreille); maxillae dentate or unarmed ; 

 labrum triangular. 



"7. Mclolonthidae, MacLeay (Phyllophagi-\; p. 

 Latreille) ; maxillae dentate ; labrnrn 

 linear or emarginate. 



t There is an evident error relative to this group in the Regrne 

 Animal, second edition, vol. iv. p. 558, line 1, where the Melu- 

 lontliidrxare referred to the Xylophili instead of the Phyllof>/iagi. 



