BUPRESTIDAE. 199 



Tribe IV.— JULOOIXI. 



The species of this trilie are convex, and of a conical form, 

 narrowed beliind, rarely cylindrical or very elongated; nearly all 

 are clothed with erect hair. The front is not contracted by the 

 insertion of the antennis; the nientum is entirely corneons ; the 

 antennal pores are diffused in the foreign genus Julodis, but con- 

 tained in marginal fovea3 in our genera. The thorax is truncate 

 at base, and closely applied to the elytra. The prosternuni is 

 broad, with the sutures oblique; the sides are not angulated be- 

 hind the coxa3, and the tip is obtusely rounded. The mesosternum 

 is deeply emarginate, rarely divided ; the niesosternal suture some- 

 times distinct, sometimes obsolete. The hind coxa; are narrow, 

 not dilated internally; the anterior margin is straight or slightly 

 concave, the hind one scarcely oblicjue ; externally they are 

 slightly wider than at the middle, and the usual prolongation of 

 the abdomen, which limits them, is covered by the elytra. The 

 epimera of the metathorax are triangular and small, but not 

 covered by the abdomen. The first joint of the hind tarsi is 

 elongated in our genera; the claws are either simjile or toothed. 



Our four genera belong to the group Acma;oderte, and might 

 be considered as types of as many sub-groups. 



Hind coxae with the anterior margin somewiiat concave ; side pieces of 

 metathorax not covered ; scutelhim visible ; claws simple Polycesta. 

 Hind coxae with the anterior margin straiglit ; 

 Claws with a broad basal tooth ; 



Scutellum indistinct ; side pieces of metathorax partly visilde. 



Acmaeodera. 

 Scutellutn visible; side pieces of the metathorax covered by the 

 elytra. Ptosima. 



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



Chrysophana. 



Polycesta and Acmaeodera 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 hairs. 



Tribe v.— MASTOOEIVIIVI. 



Mastogenius was founded by Solier upon a Chilian species : 

 the genus was subsequently^ described by Dr Le Conte as Flap- 

 lostethus, and is represented in the Southern States by 31. sub- 

 cyaneus, one of the smallest Buprestides known. 



