Jayne.] 



344 . 



in Acolpus and Trogoderma ; made up, usually, of three joints, of a vari- 

 able number of joints, however, in Perimegatoma, Acolpus, Trogoderma, 

 and Anthrenus, of two joints in Cryptorhopalum and some foreign genera, 

 and of one, enormous, securiform joint in Axinocerus. 



Prothorax short, with side pieces not separate, excavated beneath for the 

 reception of the antenna, except in Byturus, Attagenus, Dearthrus, Peri- 

 megatoma, Acolpus, and one foreign genus — Trinodes. In Anthrenus 

 the antennal fossa; divide the anterior part of the lateral margin ; coxal ca- 

 vities large, transverse, closed behind by the mesosternum, except in By- 

 turus ; prosternum prolonged behind and usually lobed in front . 



Mesosternum narrow and entire in Byturus and Dermestes ; narrow 

 and emarginate in front, or entirely divided, in Dearthrus, Perimegatoma 

 and two foreign genera — Megatoma and Hadrotoma ; wide and entire in 

 Apsectus and Orphilus ; wide and deeply emarginate, or entirely divided in 

 the remaining genera ; metasternura short, rounded or truncate in front or 

 narrowly produced between the mesocoxae ; side pieces wide, except in 

 Byturus. Elytra covering the abdomen, not striate, except faintly in cer- 

 tain species of Dermestes. Sides more regularly oval in the females ; epi- 

 pleurse not extendmg beyond. Abdomen with five free ventral seg- 

 ments. 



Anterior coxje conical, prominent, with small trochanter ; middle coxiie 

 oval, oblique, excavated externally, with large trochantin — usually dis- 

 tant, approximated in Byturus, Dermestes, Attagenus, Dearthrus, Perime- 

 gatoma and two foreign genera — Megatoma and Hadrotoma. Posterior 

 coxa slightly separated, transverse, not extending to the margins of the 

 body, except in Orphilus, dilated into a plate partly protecting the thighs. 

 This coxal plate shows a beautiful series of variations ; in B_vturus it is 

 almost obsolete ; in Dermestes and Attagenus A'er}' long, narrow, ol)liquely 

 truncate externally ; covering only the basal half of the femur ; in genera 

 from Dearthrus to Apsectus, inclusive, it is moderately long and wide, 

 covering more than the basal half of the lemur, not obliquely truncate 

 externally, while in Orphilus it is short and wide, covering the anterior 

 part of the femur for its entire length. 



Legs short, somewhat contractile, tibia; with distinct stout spurs ; tarsi 

 five-jointed, pubescent, except in Byturus, where the second and third 

 joints are lobed beneath, first joint either short or long, equaling the 

 fifth, 2-3-4 always short, fifth always long, claws simple, except in 

 Byturus, in which they are dentate. 



Two sub-families may be thus separated : 



Tarsi with second and third joints lobed beneath, 

 claws strongly toothed atbase^ mandibles toothed. 

 Anterior coxal cavities closed behind by the pro- 

 sternum BYTURID^. 



Tarsi, claws, and mandibles simple. Anterior coxal 



cavities completed behind by the mesosternum. . . DERMBSTID.S3. 



