June, 1S98.] CASEY : NORTH AMERICAN CoLEOPTERA. T 1 



apical processes long and obliquely convergent ; surface with the usual isolated 

 tubercles toward base. Elytra twice as long as wide, just visibly wider than the 

 prothorax, the apical declivity flattened, becoming alutaceous in lustre and 

 almost impunctate toward the suture, which is elevated Female. — Similar to 

 the male but larger, with the thoracic processes short and parallel, the elytra 

 rather more than twice as long as wide and more distinctly wider than the pro- 

 thorax, the apical declivity convex and coarsely perforato-punctate throughout, 

 the suture moderately elevated. Length 1 3.0-15. 5 mm. ; width 4.3-5.1 mm. 



Texas (El Paso) robustus, sp. nov. 



Vertex more tumid and convex, less finely and quite strongly punctured throughout; 

 abdomen strongly though sparsely punctured toward base ; thoracic processes 

 more approximate, separated by but little more than a fourth of the total width. 

 Female. — Head moderate in size, the eyes very convex and prominent as usual. 

 Prothorax not quite as long as wide, nearly as in robustus but less devoid of 

 sculpture toward the basal angles. Elytra not at all mere than twice as long as 

 wide, the apical declivity rather more convex at each side than in robitstus, 

 steeper and a little less coarsely punctured. Abdomen polished as usual, the 

 punctures becoming finer and denser toward apex. Length 12.5 mm.; width 

 4.3 mm. Arizona (Locality not specified — Levette Cabinet.) 



puncticeps, sp. nov. 



The male of fords has the apical processes more convergent and 

 longer than the female, but there seems to be no modification of the 

 elytral declivity near the suture. Individuals vary much in size as usual 

 in the Bostrichinse. 



Bostrichus Geoff. 



The genus Bostrichus, as represented in America, differs remark- 

 ably from Amphicerus in the structure of the antennal club, the joints 

 being short, subglobose, and with the sensitive spaces small and circu- 

 lar ; jt also differs in having the basal angles of the prothorax acute and 

 prominent, but in that respect resembles Apatides, from which it differs 

 in turn in the structure of the antennal club and frontal parts of the 

 head. The following table comprises all the species known to me at 

 present : — 



Prothorax narrowly and deeply sinuate at apex, with the limiting processes promi- 

 nent and generally unciform ; elytra each with two ridges more or less distinct 

 or interrupted 2 



Prothorax sinuato-truncate at apex, with the limiting angles acute and somewhat 

 prominent ; vestiture hair-like, decumbent and unevenly distributed ; elytra 

 without trace of ridges ; species smaller and more slender 5 



2 — Hind tarsi fully as long as the tibioe ; unciform processes of the prothorax more 

 prominent. Atlantic regions 3 



Hind tarsi shorter than the tibiee ; unciform processes shorter, not differing in form 

 lrom the lateral senules 4 



