386 INSECT A. 



but very slightly in both sexes; the length of the last joint is never 

 much greater than that of the preceding ones. 



Certain species ao great injury among furs, and devastate our col- 

 lections of natural history. De Geer calls them dissectors, and in 

 fact the Derrnestes lardarius cuts to pieces the Insects of the cabinet 

 into which it has penetrated. The others devour the dead bodies of 

 all kinds of animals. 



D. lardarius, L.; Oliv., Col., II, 9, I, 1. Black; base of the 

 elytra cinereous and dotted with black. The larva is elongated, 

 insensibly tapered from head to tail, of a chesnut-brown above, 

 white beneath, furnished with long hairs and two squamous 

 horns on the last annulus. Its excrements resemble long 

 threads(l). 



Megatoma, Herbst. Lin. Geoff. Fab. 



The Megatomx only differ from Derrnestes in the club of their 

 antennae, which is much more elongated in the males than in the 

 females; the terminal joint is lanceolate or forms an elongated tri- 

 angle. 



M. pellio; Derrnestes pellio, L.; Oliv., lb., II, ii. But two lines 

 and a half in length; black; three white dots on the thorax, and 

 one on each elytron, formed by down. The larva is greatly 

 elongated, of a glossy reddish-brown, and covered with reddish 

 hairs, those of the posterior extremity forming a tail. It moves 

 by sliding, and as if by jerks, which is also the case with the 

 perfect Insect, and the Dermestes(2). 

 In others, such as 



Limnichus, Zieg. Dej., 



The antennse become gradually thicker, and terminate in a larger 

 and ovoid joint; they are granose, and received under the anterior 

 angles of the thorax. The maxillse are terminated by two lobes, 

 the exterior of which is narrow and palpiform. The labial palpi 

 are very small; the last joint of those of the maxillae is larger than 

 the preceding ones and ovoid(3). 



In all the following subgenera, the antennse, or at least their club, 

 are received into particular and lateral cavities in the under part of 



(1) Add D. vulpinus, murinus, ajjinis, laniarius, tesselatus, trifasciatus, Gyll , 

 Insect. Suec, I, p. 145, et seq. 



(2) Add the Derrnestes megatoma, Fab., of which his macellarius appears to be 

 the female; D. emarginatus, Gyll.; D. undatus, Fab. The presternum in this 

 latter species projects over the mouth. 



(3) Byrrhus sericeus, Duft. ; B. pygmasus, Sturm. 



