BUPItESTIDAE. 155 



Our four genera belong to the group Acniseoderse, and might 

 be considered as types of as many sub-groups. 



Hind coxa? with the anterior margin somewhat concave ; side pieces of 

 metathorax not covered ; scutellum visible ; claws simple. Polycesta. 



Hind coxae with the anterior margin straight ; 

 Claws with a broad basal tooth ; 

 Scutellum indistinct ; side pieces of metathorax partly visible. 



ACMiEODEKA. 



Scutellum visible ; side pieces of metathorax covered by the elytra. 



Ptosima. 

 Claws simple ; scutellum visible ; side pieces of metathorax visible. 



Chrysophana. 



Polycesta and Acmreodera are found on both sides of the conti- 

 nent, Ptosima in the Atlantic States, and Chrysophana in Oregon ; 

 the last genus is entirely glabrous above, the others are clothed 

 more or less densely with erect hair. 



Tribe IV.— HAPLOSTETHLtfl. 



This tribe contains but a single species from the Atlantic 

 States, Haplostethus subcyaneus Lee, and is the smallest Bu- 

 prestide known. The form is cylindrical, and resembles some- 

 what certain Acma?odera3 ; the color is bluish black. 



The antennas are inserted in cavities narrowing the front, which 

 does not expand again anteriorly, as in the next tribe ; the mouth 

 is small, deflexed, but not applied to the prosternum ; the meiitum 

 is entirely corneous. The prothorax is truncate at base, closely 

 applied to the elytra. The prosternum is broad, truncate before 

 and behind, with the lateral sutures parallel. The mesosternum 

 is not visible ; the metasternum is broadly truncate in front, and 

 applied to the prosternum ; the epimera of the metasternum are 

 triangular, not covered by the abdomen. The hind coxa? are not 

 dilated inwards, slightly broader outwards, and extend to the 

 elytra; the anterior margin is slightly concave, the hind one not 

 oblique. The legs are not contractile ; the claws are broadly 

 toothed. 



Tribe V.— AGRILIJVI. 



In this tribe the body is usually slender, sometimes, however, 

 very broad and fiat; in both cases it is narrowed behind. The 

 species are found on leaves and flowers. 



The front is strongly narrowed by the insertion of the antenna?, 



