OF WASHINGTON, VOLUME XIV,^1912. 27 



numerous other insects found in their galleries is still an open 

 question. The larva is also so far unknown. 



In the following synopsis and descriptions thesutural inter- 

 space in either elytron is considered as the first. The odd 

 interspaces (1, 3, 5, 7, etc.) are always the more elevated, 

 while the even (2, 4, 6, etc.) are frequently so flattened and 

 unarmed as to appear obsolete, or nearly so, and in such in- 

 stances the intervals between the costae have apparently a 

 double row of punctures, which character is frequently men- 

 tioned in former descriptions. In no instance are the even 

 interspaces truly obsolete, however, and I have mentioned 

 them throughout the descriptions. 



The locality given under each species is the t\pe locality. 

 A full list of localities from which specimens were at hand is 

 given at the end of the brief summary of each species follow- 

 ing the synopsis: 



SYNOPSIS OF SPECIES. 



Pronotum subquadrate, with a distinct broad longitudinal im- 

 pression just within the side margins, extending from an- 

 terior to posterior margin DIVISION I 



Pronotum of varying shape, very narrowly or not at all margined, 

 never with broad longitudinal impression from posterior to 

 anterior margin DIVISION II 



DIVISION I. 



Interspaces 1, 3, and 5 equally elevated from base to apex; prono- 

 tum subquadrate, its side margins straight, not narrowed 

 behind SUBDIVISION A 



Interspaces 3 and 5 more elevated than 1, and 3 decidedly more 

 elevated from vertex to apex than 5; prothorax more or less 

 narrowed posteriorly SUBDIVISION B 



SUBDIVISION A. 



Length 2.5 mm. Light ferruginous, elytra parallel, even inter- 

 spaces appearing obsolete, margins of head very strongly 

 reflexed, front granulate, with a prominent acute longi- 

 tudinal median tubercle, pronotumas wide as elytra at base, 

 pronotum with two pairs of longitudinal costas, the outer 

 pair nearly straight on anterior margin, joined in a broad 

 U curve to the middle pair, the latter tortuous, broken at 

 posterior 34, but continued parallel and in closer approxima- 

 tion to the posterior margin, where they are joined by a 



transverse ridge mexicanus, n. sp. 



Mexico (Guanajuato.) 



