Casey — Observations on the Staphylinidae: 361 



markable deep groove, with which perhaps the hiteral line of 

 Leptacinus is homologous, and outside of which the lateral 

 line of the head is acute and prominent inferiorly ; above this 

 line the surface is evenly convex through the flanks to the dor- 

 sal surface and without further irregularity. The gular su- 

 tures are single from the small triangle behind the mentum 

 to the base, the neck scarcely a third as wide as the head, the 

 third palpal joint elongate, obconical, the fourth small, slender 

 and oblique and the mandibles are rather small, arcuate, each 

 strongly unidentate within, convex externally, with a fine im- 

 pressed longitudinal groove. The antennae are shorter than 

 the head, broadly flattened, glabrous but with herissate setae 

 and are wholly unique in the tribe. The prothorax and pro- 

 sternum are nearly as in Gyrohypnus, but the bevel of the inner 

 edges of the elytra is convex, rather narrow and not marked 

 by a carina or elevated beading at its upper part. The tarsi 

 are remarkably long and slender, with the basal joint much 

 shorter than the second ; the middle tarsi are notably longer 

 than the tibiae. 



A considerable number of neotropical species have been 

 placed in Metoponcus, chiefly by Dr. Sharp, but they probably 

 constitute several distinct genera, no one of which is exactly 

 congeneric with the European Metoponcus, although longiceps 

 Shp., may possibly form a genus of the subtribe Metoponci as 

 here considered, on account of the peculiar form of the in- 

 terantennal epistoma. The remarkable antennal structure of 

 Metoponcus, which constitutes one of the most distinctive 

 features of the present subtribe, has been unaccountably 

 overlooked in describing these neotropical forms, some of 

 which may enter Oligolinus, defined below to receive the 

 Metoponcus floridanus, of LeConte, the antennae of which 

 are certainly not Metoponcid. 



Hyptiomae. — This subtribe is founded upon a single very 

 small slender and strongly depressed parallel species, occur- 

 ring in the Island of Cuba, which may be described as 

 follows : — 



Strongly depressed, parallel, pale testaceous in color, the legs and an- 

 tennae also pale, the head blackish, moderately shining. Head sub- 



