Casey — Observations on the Staphylinidae. 387 



Groups I and II correspoud satisfactorily with palaearctic 

 species of the punctulalus and angustatus type, but the last 

 two groups are probably peculiar to America. The rather 

 numerous species may be defined as follows : — 



Group I. 



Color black or piceous-black, the elytra generally paler in part 3 



Color testaceous or piceo -testaceous, the head black or blackish 5 



2 — Elytra black throughout. Body stout, narrowed anteriorly, moder- 

 ately convex, deep black throughout, the antennae black, the legs 

 dark piceo-testaceous; lustre shiuing; head small, rather longer than 

 wide, parallel and straight at the sides, truncate at base, the angles 

 narrowly rounded, the median parts smooth, the punctures coarse, deep 

 and notably close-set toward the sides; flattened line behind the eyes 

 densely, rather coarsely punctate, concave posteriorly, the edges be- 

 coming acute and very distinct; under surface elevated along the gular 

 sutures, rather coarsely, closely punctate; prothorax obviousiy wider 

 than the head, but slightly longer than wide, the angles broadly rounded ; 

 sides moderately converging and somewhat arcuate; aerial punctures 

 coarsely impressed, the dorsal series ending at basal third, with its 4-5 

 punctures very evenly spaced; sublateral series of 5-6 punctures and 

 some scattered punctures near the anterior angles distinct; elytra 

 quadrate, as long as the prothorax and much wider, coarsely punctate, 

 each with two medial close -set series, unevenly punctured toward the 

 sutare; abdomen finely, rather sparsely punctulate. Length 6.7 mm. ; 

 width 1.2 mm. New York, Canada, Iowa, Lake Superior, Manitoba, 

 Nevada (Reno) and Oregon (Albany). [=americanw* Dej., i. litt.]. 



obsidianns Mels. 

 Elytra piceous, with the sides and tip piceo-testaceous. Body more slender 

 than in obtidiamis, piceous, the legs and antennae piceo-testaceous; 

 head moderately convex, smooth, sparsely and coarsely punctured at 

 the sides, the under surface very sparsely punctured, the sides with a 

 broad shallow longitudinal groove which is distinctly margined and 

 marked with a few shallow punctures; prothorax with the dorsal 

 series 4-5 punctured, the lateral series punctured, with a large punc- 

 ture nearer the margin as usual; elytra sparsely and coarsely punctate, 

 the punctures arranged in nearly regular rows. Length 4.7 mm. 



Forida (Cedar Keys). [=floridae Duviv.] temporalis Lee. 



Elytra pale testaceous or yellowish, more or less gradually darker in about 



basal half 3 



8 — Sublateral series of the pronotum 7-9 punctured. Body more slender 

 ihsin Xantholinus picipennis, piceoas-h\ack, the antennae and legs dark 

 ferruginous, the elytra ferruginous, blackish in about anterior half; 

 head moderately convex, rather elongate, the hind angles rounded; 

 npper surface smooth at the middle, sparsely and coarsely punctured at 

 the sides; frontal grooves as usual; under surface very sparsely and 



