122 MEMOIRS ON THE COLEOPTERA. 



minute, not dens? and scarcely at all asperulate; head nearly as long as 

 wide, the eyes rather small, at more than their own length from the base, 

 the tempora parallel, feebly arcuate and as prominent as the eyes, the carinae 

 feeble but about entire; antennae rather short, gradually incrassate, the 

 outer joints nearly twice as wide as long, the second as usual longer than the 

 third, the last obtuse, not longer than the two preceding; prothorax rather 

 convex, scarcely one-half wider than long, parallel, with rounded sides and 

 rounded base, much wider than the head and perceptibly narrower than 

 the elytral base, the median line very obsoletely impressed basally; elytra 

 large, slightly abbreviated, with feebly diverging sides, the suture impressed 

 basally and fully one-half longer than the prothorax; abdomen much nar- 

 rower than the elytra, parallel, not narrowed apically. Length 1.4 mm.; 

 width 0.3 mm. California (Pomona, Los Angeles Co.), Fall. 



At least subgenerically distinct from the preceding. The types 

 are females. 



Datomicra diffidens n. sp. Slender, rather convex, strongly shining, 

 black, the elytra and legs dark piceous; punctures minute, not very close- 

 set, slightly asperate only on the elytra; head much wider than long, rounded 

 at the sides, the eyes large, at about half their length from the base, the 

 carince entire; antennae piceous, of the usual structure and rather short, 

 unusually slender, the outer joints but slightly transverse, the last barely 

 as long as the two preceding, pointed; prothorax very moderately trans- 

 verse, subparallel, with strongly rounded sides, much wider than the head 

 and only just visibly narrower than the elytral base, the apex very slightly 

 narrower than the base, the surface not impressed along the median line 

 but with a small rounded basal pit; elytra only moderately transverse, 

 parallel, the suture a third longer than the prothorax; abdomen rather long, 

 parallel, almost imperceptibly narrowed at apex, narrower than the elytra. 

 Length 1.38 mm.; width 0.28 mm. New York (Catskill Mts.). 



Distinguishable readily by the lustre, form of the prothorax and 

 the slender antennae. The type seems to be a female. 



Datomicra vacans n. sp. More minute, black, the elytra and legs blackish- 

 piceous, not notably shining, the punctures very close-set and strongly as- 

 perate throughout, less close but even more asperate on the more shining 

 abdomen; head slightly wider than long, convex, impressed along the median 

 line, parallel, the eyes at nearly their own length from the base, the carinae 

 entire; antennae rather short, moderately incrassate, of normal basal struc- 

 ture, the outer joints about two-thirds wider than long on the compressed 

 side and barely one-half wider than long on the narrow side, the last as long 

 as the two preceding; prothorax moderately transverse, parallel and moder- 

 ately arcuate at the sides, only a little wider than the head and slightly 

 narrower than the elytra, the median line distinctly impressed throughout; 

 elytra short and transverse, truncate, the suture scarcely a fifth longer than 

 the prothorax; abdomen narrower than the elytra, the sides just visibly 

 converging from base to apex, the fifth tergite (<f) with a minute discal 

 spinuliform tubercle near the apex, the sixth with two medial teeth, 



