136 Trans. Acad. Sci. of St. Louis. 



the apex, gradually formed, with the angle distinctly rounded, the lobes 

 of the apex evenly and rather strongly rounded. Length 4.6-5.4 mm. ; 



width 0-88 mm. Iowa and Nebraska (Lincoln) gracilicornis n. sp. 



Antennae distinctly less than half as long as the body; the medial joints less 

 elongate 4 



4 — Prothorax smaller when compared with the elytra, its sides frequently 



almost straight 5 



Prothorax larger, the sides parallel and always distinctly arcuate 6 



5 — Prothorax parallel and broadly arcuate at the sides; body moderately 



stout, convex, polished, bright rufous, the legs and antennae pale, the 

 head black, the abdomen piceous-black, dull rufescent at tip; head as 

 long as wide, parallel and straight at the sides, with broadly rounded 

 basal angles, coarsely and sparsely punctate; antennae in the male as 

 long as the prothorax and elytra combined, only moderately slender, 

 scarcely at all incrassate, the medial joints three-fourths longer than 

 wide, a little shorter and thinner in the female; prothorax in the male 

 only slightly elongate, rather distinctly wider than the head, finely but 

 distinctly, very sparsely punctate, the punctures irregularly subserial 

 along the smooth area, narrower in the female, with the sides almost 

 straight; elytra distinctly longer than wide, the sides subparallel and 

 almost straight, fully two -fifths wider and longer than the prothorax 

 in both sexes, the punctures not coarse but distinct, arranged in regu- 

 lar and scarcely impressed series almost throughout; abdomen much 

 narrower than the elytra, densely punctulate. Male with the fifth 

 ventral unmodified, the sixth glabrous and very faintly impressed along 

 the middle, the apex with a very small triangular emargination, slightly 

 wider than deep, with its angle narrowly rounded, about a sixth 

 or seventh as wide as the apex, the lateral lobes strongly rounded ; 

 female with the sixth ventral broadly parabolic at tip. Length 5.7 

 mm.; width 0.95 mm. Oregon oregonensis n. sp. 



Prothorax parallel and virtually straight at the sides — at least in the 

 female; — body rather more slender and parallel, bright rufous through- 

 out, except the head which is black, the piceous-black abdomen rufes- 

 cent at tip; head rather well developed, somewhat wider than long, 

 parallel at the sides, the basal angles only moderately broadly rounded ; 

 eyes rather prominent, well developed, the punctures coarse and sparse; 

 antennae in the female but little longer than the head and prothorax, 

 rather thick, distinctly incrassate distally, the medial joints two-thirds 

 longer than wide; prothorax distinctly elongate, only slightly wider 

 than the head, the sides subparallel and straight, the punctures un- 

 usually coarse, deep and conspicuous and only moderately sparse; 

 elytra parallel, slightly elongate, a third wider and longer than the 

 prothorax, with moderate punctures not very close-set in regular 

 impressed series, confused toward tip ; abdomen distinctly narrower 

 than the elytra. Male unknown. Length 5.5 mm.; width 0.9 mm. 

 Tennessee (Nashville") f allax n. sp. 



6 — Antennae nearly half as long as the body, rather thick, distinctly 

 incrassate distally, the medial joints only slightly less than twice as 

 long as wide; head small, as long as wide, parallel at the sides, the 

 angles broadly rounded, the punctures coarse and sparse; prothorax a 



