Casey — Obseroations on the Staphylinidae. 263 



narrow ; hypomera long and well developed ; head short and moderately 

 narrowed behind the eyes, which are large and prominent; neck very 

 broad ; pronotal punctures fine and asperate ; tarsi very slender, the 

 basal joint of the posterior as long as the next two combined or longer. 



Nearctic Atlantic regions Yennsa 



Fourth antennal joint large, wider than the preceding joints and aubsimilar 

 to those which follow; general form of the body as in Venusa, the pale 

 maculation of the elytra usually more distinctly defined, the pronotal 

 punctures less asperate and nearly simple; head, eyes, neck and hypo- 

 mera nearly similar, the mesosternal process broader, very obtuse at 

 tip, almost attaining the metasternum; tarsi rather less slender, the 

 basal joint of the posterior barely as long as the next two combined, 

 Nearctic Atlantic regions Plenrotobia 



In addition to the two characters previously mentioned 

 which distinguish these genera of the first group from 

 Silusa, Leptusa and others of the second group, it should be 

 said that the elytra here are always variegated with dark or 

 black and pale tints, the humeri at least being invariably 

 paler than the external apical parts, but, in the second group, 

 the coloration of the elytra is uniform, any variegation being 

 feebly developed and exceptional. The three exclusively for- 

 eign genera of the table may be remarked upon as follows : — 



BoLiTOCHARA Mann. — This genus may be recognized at 

 once by the obsolete infra-lateral carinae of the head, so uni- 

 versally developed elsewhere in the subtribe, except in certain 

 very slender and almost blind species of Sipalia^SMoh. as Jlava 

 Kr. ,pIicateUa Fauv.and bituberculata a.nd arida Epp., which, 

 because of the narrow subelongate head, frequently very 

 minute subfacetless eyes and complete absence of the infra- 

 lateral carinae should be generically separated from Sipalia, 

 and for which I would propose the generic name Typhlusida. 

 With this virtual absence of the carinae in Bolitochara, 

 occurs the seemingly correlated narrow neck, which is wholly 

 foreign to any of the American genera. Bolitochara, as here 

 restricted, is represented by such European species a.a lunulafa 

 Payk., and lucida Grav. 



DiTROPALiA n. gen. — The complete infra-lateral carinae of 

 the head is a perfectly constant and very important character, 

 separating this genus from Bolitochara. The head behind 

 the eyes is, however, more strongly narrowed and more elon- 



