184 CUKCULIONID^. [LeConte. 



The species may be tlins separated : 



Third joint of tarsi broader, emarginate 2. 



" " narrow, not emarginate 5. 



2. Elytra each with one posterior tubercle 3. 



" two " tubercles 1. mamraillatus. 



3. Interspaces equal, flat, or nearly so 4. 



Alternate interspaces more elevated 2. sellatus. 



4. Scales uniform pale gray, striai less deep 3. planatus. 



" gray and dark brown ; strine deeper 4. obliquus. 



5. Tarsi very long, prothorax finely rugose 5. americanus. 



" short ; prothorax scarred with deep im- 

 pressions 6. 



Tarsi short, or moderate, prothorax strongly 

 granulate 7. 



Tarsi short, or moderate, prothorax feebly granu- 

 ulate 8. 



6. Front deeply excavated, beak tricarinate., 6. cavifrons. 



" foveate, beak tricarinate 7. magister. 



7. Elytra clouded with darker scales ; beak long, 



tarsi short 8. iiebulosus. 



Elytra uniform in color ; beak short, tarsi long. . 9. californicus. 

 " with a white spot behind, beak short, tarsi 



long 10. restrictus. 



Elytra with a broad black band, beak short, tarsi 



long 11. pusillus. 



8. Prothorax not transverse 12. bituberosus. 



" wider than long, much constricted in 

 front 13. transversus. 



1. B. mammillatus Say, Cure. 28, ed. Lee. i, 297; Gyll., Sch. Cure, 

 iii, 539. 



Southern and Western States. Varies in size from 2.4-3 mm.; .09-1.3 

 inch. 



2. B. sellatus, n. sp. 



Black; head, three thoracic vitta3, sides and tip of elytra densely cov- 

 ered with cinereous scales, leaving a large elongate common triangular 

 space black. Prothorax a little longer than wide, coarsely granulate, sides 

 parallel, suddenly constricted near the tip. Elytra with the humeri oblique 

 and obtusely angulated, striae deep, interspaces convex, first, third, and 

 fifth more elevated, the last terminating in a large conical tuberosity, which 

 is surrounded behind by a dark cloud. Beneath fuscous, thighs with a 

 ring of paler scales. Tarsi with the third joint broader, emarginate. 

 Length 2.5 mm.; .10 inch. 



One specimen, Georgia. The common triangular spot extends from the 

 humeri to the suture upon which it ends at about two-thirds the length ; 

 there is also on each elytron a marginal cloud behind the humerus, and a 

 small subapical one behind the large tuberosity. 



