Casey — Observations on the Staphylinidae. 281 



ments, regular system of punctuation, short elytra and small 

 size, some of them being so minute as to be comparable only 

 with Ftilium, of the Trichopterygidae. The secondary male 

 sexual characters are frequently complex, consisting of small 

 spines or protuberances on the dorsal surface of the abdo- 

 men, but, in other forms, these secondary characters are very 

 feeble. The species are moderately numerous, those before 

 me at present being separable by the following characters : — 



Antennae pale In color 2 



Antennae black or blackish beyond the fourth joint 12 



2 — Species less minute, about 1.0 mm. or more in length 3 



Species very minute, much under 1.0 mm. in length 11 



8 — Small asperate punctures of the elytra very sparse; male with strongly 

 marked secondary sexual characters. Form rather stout, subparallel, 

 convex, shining, blackish-piceous in color, the elytra very slightly 

 paler, uniform; abdomen black, especially behind; integuments rather 

 coarsely micro-reticulate throughout, the pubescence very short, 

 sparse and Inconspicuous; head transverse, finely, sparsely punctate ; 

 prothorax twice as wide as long, a third or fourth wider than the head, 

 widest near the base, the sides arcuate, ^the surface minutely, very 

 sparsely punctate throughout, with a small rounded impression before 

 the scutellum; elytra strongly transverse, slightly wider and longer 

 than the prothorax; abdomen not quite as wide as the elytra, parallel; 

 legs short, slender, pale. Male having a short erect spiniform process 

 at the middle of the apex of the first tergite, flanked on each side by a 

 very minute marginal angulation, the fourth tergite with two small, 

 suberect, spiniform processes on the disk just before the apex, sepa- 

 rated by about a seventh of the total width of the plate, the fifth with 

 two small and more obtuse, obliquely cariniform processes, more 

 approximate and at a greater distance from the apex; sixth angulate at 

 tip, the angle reflexed. Length 1.0-1.5 mm.; width 0.35-0.45. mm. 

 New York (Catskill Mts.), District of Columbia, Missouri (St. Louis) 



and Texas (Dallas). [ = Gyrophaena corr. Er.] corrnscnia Er. 



Small asperate punctures more close -set; male with feeble secondary sexual 



characters, chiefly affecting the emargination of the sixth tergite 4 



4 — Elytra black, the humeri testaceous. Body stout, compact, polished, 

 micro -reticulate throughout, the lines fine; color dark testaceous, the 

 abdomen clouded with blackish except toward base; head large, 

 sparsely punctate at each side of the median line; prothorax transverse 

 but not quite twice as wide as long, only very slightly wider than the 

 head, finely, sparsely, irregularly punctate at each side of the impunc- 

 tate median line, not impressed before the scutellum, the base rather 

 strongly arcuate; elytra strongly transverse, a fifth wider and fully a 

 fourth longer than the prothorax, finely, not very closely, asperulately 

 punctate; abdomen at base almost as wide as the elytra, narrowed and 

 arcuate at the sides thence posteriorly ; legs short, slender, pale flavate 

 in color. Male with the sixth tergite broadly produced at apex, the 



