The species here described somewhat superficially resembles Staphylinus cinnamopterus Grav., yet appears distinct and to be hitherto uncharacterized. In admiration of Professor J. H. McGregor of Columbia University, and in appreciation of kindnesses tendered me, I propose to name this new form:

Staphylinus macgregori n. sp.

Habitus nearly as in cinnamopterus but larger in size and rather more robust; piceous, the elytra fusco-ferrugineus, the legs fulvo-ferrugineus ; pubescence inclined, on the head, thorax, and elytra of a rusty hue and with few erect, brown setae, on abdomen fusco-piceous pubescence intermixing with fewer rusty-colored hairs and an abundance of dark setae; anterior tarsi broadly dilated in both sexes ; head slightly narrower than prothorax, widest at basal fourth thence gradually narrowing anteriorly, hind angles obtusely prominent, punctures round and ocellate throughout, close-set but clearly separated by shining interspaces, sparser anteriorly; mandibles longer and more slender than in cinnamopterus, the two inner teeth much less prominent and more poorly developed; antennae piceous to fuscopiceous, a third longer than head; prothorax but slightly wider than head, truncate at apex, rounded at base, punctures ocellate, more elongate at the sides than those of head and somewhat larger, smaller and more closely set than in cinnamopterus but separated by shining interspaces, the median line evident, polished, but very narrow throughout, in places ill-defined or obliterated; scutellum velvety black; elytra fusco-ferrugineus, longer than wide, very finely but strongly and densely punctate, clothed with a decurved rusty-colored pubescence similar to that of head and thorax but more dense; abdomen obscurely fulvous at tip, piceous, coriaceo-reticulate and very sparsely and finely punctate at sides, with median velvety fuliginous spots suffering intermixture of short cinereous hairs at the sides; under surface of abdomen clothed with sparse, long, depressed, fuscs-piceous pubescence, coriaceo-reticulate, punctures very fine and sparse, slightly less sparsely distributed at sides of segments, the male fifth ventral with a very broad circular and feeble sinuation medially, the male sixth ventral obscurely fulvous at tip and with a broad, rounded, median emargination about one half as deep as long, fifth ventral of female truncate, sixth female ventral rounded evenly and fulvous. Length ( ) 10.0-12.7 mm.; width 3.0-3.3 mm.