STAPHYLINID^E. 23 



than the prothorax; abdomen perfectly parallel, much narrower than the 

 elytra, the first three tergites strongly impressed, the sixth (cf) broadly 

 lobed at apex, the lobe arcuato-truncate, with a faint median projection, 

 the apex at each side of the base of the lobe feebly concave; mesosternal 

 process rather broad and truncate at apex, extending to the middle of the 

 separated coxae and considerably distant from the apex of the elongate meta- 

 sternal projection, which has its apex rounded ; hind tarsi rather short, the 

 first four joints equal. Length 2.2 mm. ; width 0.6 mm. Ohio (Cincinnati), 

 Dury. 



This remarkable species can be known at once by the elytra of 

 the male, each having a distinct umboniform tubercle just before 

 the middle and at inner third; the absence of cephalic carinae and 

 rather wide truncate mesosternal process are also conspicuous dis- 

 tinctive characters. 



Atheta nevadensis n. sp. Elongate, very moderately convex, polished 

 throughout, the micro-reticulation obsolescent; color piceo-testaceous, the 

 head and abdomen blackish; legs pale, the antennae dark brown throughout; 

 vestiture rather short and not at all dense; head orbicular, the eyes at rather 

 more than their own length from the base, the carinae fine and not extending 

 before the middle; antennae gradually thick and very strongly incrassate, 

 the outer joints slightly transverse, the eleventh rather longer than the two 

 preceding, the second and third equal; prothorax moderately transverse, 

 much wider than the head and correspondingly narrower than the elytra, 

 parallel and strongly rounded at the sides, very finely, sparsely punctulate, 

 the basal impression somewhat rounded, very feeble; elytra but slightly 

 transverse, very much longer as well as wider than the prothorax, minutely, 

 not densely punctulate; abdomen parallel, slightly narrower than the elytra, 

 sparsely, very finely punctulate, the fifth tergite very slightly longer than the 

 fourth, the sixth (cf) truncate and very finely and feebly crenulate at tip; 

 mesosternal process extending beyond the middle of the slightly separated 

 coxae, the apex attenuate and very finely aciculate, separated from the very 

 short and broadly rounded metasternum by a long depressed smooth ridge; 

 posterior tarsi rather long, the first four joints equal. Length 3.2 mm.; 

 width 0.73 mm. Nevada (Reno). 



The elongate form, shining integuments, rather small and trans- 

 versely oval prothorax, feeble male sexual characters, thick and 

 incrassate antennae and sternal structure will render the identifica- 

 tion of this species comparatively easy. 



The following thirteen species are small forms, apparently in- 

 habiting fungi, having pale elytra and legs, the abdomen more or 

 less evidently paler basally, the antennae moderately stout and 

 subparallel except basally, or, at most, very moderately incrassate, 

 and with the sixth tergite of the male auriculate at the sides of the 

 apex, with the intervening edge in no case crenulate. These are 



