COLEOPTERA. BYRIUIID.'E. 179 



nearly with the Linnaean genus Byrrhus. The body is short, oval, or 

 rounded, very convex, and generally covered with short sericeous pile 

 {Jig. 17. 9. Byrrhus pilula, 17. 10. labrum, 17. il- mandible, 17. 12. 

 maxilla, and 17. 13. labium of the same). The antennae are more or 

 less gradually clavate, the club not being solid {fig. 17. 14.) : the pro- 

 sternum is produced in front {fig. 17. 15. body beneath) ; the elytra 

 cover the body ; the legs are perfectly contractile, that is, the tarsi are 

 capable of being laid closely upon the surface of the tibiae which are 

 broad and compressed ; and the latter upon the femora, which, when 

 the insect is alarmed, are entirely lodged in cavities on the under side 

 of the body for their reception {fig. 17. 15. and 17. 16. hind leg par- 

 tially shut up, and seen from within). 



These insects are found on the ground, especially in sand pits in the 

 spring, in foot-paths, &c. ; on the slightest approach of danger they 

 instantly fold up their antennae and legs as above described, and which 

 are thus so completely concealed that the insect appears more like 

 an oval seed or pill, whilst thus counterfeiting death as their means of 

 defence : hence the common name of Pill-beetle which has been applied 

 to them. Some species (Nosodendron, Trinodes) are found under the 

 bark of decaying trees in situations where there is an exudation of sap. 



The larvffi of a variety of the common species (Byrr. pilula), dis- 

 covered by M. Wandouer in moss, is mentioned by Latreille as being 

 of a lengthened and narrow form, with the head large, the dorsal 

 plate of the first segment large, and the two terminal segments larger 

 than the others. Mr. Ingpen has communicated to me specimens of 

 a larva {fig. 17. 17.), three quarters of an inch long when alive, found 

 creeping about the foot of the iron palisades of one of the squares in 

 London, and which agrees with the description given by Latreille : 

 the body is long, narrow, and subcylindric, with the head and large 

 dorsal plate of the first thoracic segment horny ; the nine following 

 segments are short, and of a more membranous consistence, with a 'i&w 



Goeze, in Naturforsclier, St. 8. 



Hope, in Trans. Ent. Soc. No. 1. ( Microclicetes). 

 Germar. Insect. Sp. Nov. (Ceutoccrus). 

 O. Fabricius, in Mem. Soc. Hoy. Denmark. 

 Charpentier. Hora; Ent. 



Dufour, in Ann. Sc. Nat. 2d series, vol. j. p. GO. ; and tlie general works of Gylltn- 

 haU, PaykuU, Stephens, Curtis, 8fc. 



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