464 INSECTA. 



The eighth tribe, that of the Byrrhii, differs from the preceding 

 in the perfect contractility of the legs ; the tibiae are susceptible of 

 being flexed on the thighs, and the tarsi on the tibiae *, so that when 

 thus folded and pressed against the body, the animal seems to be in- 

 animate and entirely destitute of feet. The tibiae are usually broad 

 and compressed. The body is short and convex. 



This tribe is chiefly composed of the genus, 



Byrrhus, Lin. 

 Those species which form the 



NOSODENDRON, Lut. 



Are removed from the others by their entirely exposed, very large, 

 and scutiform nientum. Their antennae terminate abruptly in a 

 short, perfoliaceous and triarticulated club. They are found in 

 wounds of trees, of the elm particularly f. 



Byrrhus, Lin. — Cistela, Geoff. 



The true Byrrhii differ from the preceding Insects in their men- 

 turn, Avhich is of an ordinary size and interlocked (at least partially) 

 by the prcesternum, whose anterior extremity is dilated. 



In some, the antenncc enlarge insensibly, or terminate in an en- 

 gated club formed of from five to six joints. 



B. pilula,L.; Oliv., Col. II, 13, 1, 1. From three to four 

 lines in length ; black beneath, blackish-bronze or soot colour 

 and silky above, with little black spots mingled with lighter ones 

 arranged in lines. 



M. Waudouer has detected the larva of a variety of this spe- 

 cies. It is narrow and elongated ; the head thick ; the plate of 

 the first segment large, and the two last longer than the others. 

 It lives in Moss. 



A second species — striata punctatus, Dej. — with similarly 

 formed antennae, constitutes a separate division, on account of 

 its tarsi, of which the fourth joint is very small and concealed be- 

 tween the lobes of the preceding one. 



The antennae of another species, very small and covered with 

 hairs, terminate in a triarticulated club. It forms the genus 

 Trinodes, Megerl., and Dej. +. 



On similar grounds we might alse separate from the Byrrhii 

 some other analogous species ||, in which the antennal club con- 

 sists of but two joints, the last much the thickest and nearly glo- 

 bular. 



* In tlie Antlireui all the tibiee fold against the posterior side of the thighs ; but 

 in the others, the two that are anterior are flexed towards the head, and the other 

 behind. 



t Lat., lb., II, p. 4,3 ; Oliv., Encyc. Mothod., article Nosodendre. 



t Anthrenus hirtus, Fab.; Panz., Faun. Insect. Germ., XI, 16. 



II Byrrhus erinaceus, Ziegl. ; — B. setiger, Illig. 



