310 MEMOIRS ON THE COLEOPTERA 



the sides feebly converging from base to apex, the latter two-thirds 

 as wide as the base and deeply sinuate, the angles prominent and 

 but slightly blunt, the basal right, the puncture but little nearer 

 base than side; impressions obsolete, the stria very fine; foveae very 

 feeble and indefinite, the outer oblique when present, the short in- 

 cised dash of the inner evident; elytra barely visibly wider than the 

 prothorax, the sides rather rapidly and obtusely rounding behind; 

 lateral series not interrupted, although remotely spaced medially; 

 striae fine, impunctate, the two inner a little coarser behind, the 

 seventh feeble, the scutellar long, barely oblique, free at tip; inter- 

 vals flat or nearly so in both sexes. Length (cf 9 ) 8.0 mm.; width 

 3.5-3.7 mm. Wyoming impedita n. sp. 



Sides of the prothorax more arcuate anteriorly than posteriorly, as usual 

 in the genus 31 



31 Body larger, stouter, oblong-oval and very convex, deep black, feebly 

 shining and without trace of metallic lustre, the elytra strongly micro- 

 reticulate and alutaceous in the female; under surface deep black, 

 the legs piceous, with blacker femora. Head fully half as wide as the 

 prothorax, the eyes only feebly convex, the strides subobsolete; 

 antennae extending to the thoracic base in the female, slender, only 

 feebly compressed, black, the first two joints obscure rufous, the 

 third piceo-rufous, the second and third strongly carinate; prothorax 

 three-fifths wider than long, the arcuate sides becoming straighter 

 but not parallel basally; apex nearly three-fourths as wide as the 

 base, moderately sinuate, with blunt angles, the basal right, the 

 puncture rather small, equally distant from base and side; impres- 

 sions very feeble, the stria fine and feeble; foveae broad and faintly 

 impressed, the incisure of the inner very short; elytra subequal in 

 width to the prothorax, evenly ogival in apical two-fifths, about 

 one-half longer than wide; striae very fine, coarser on the declivity, 

 the seventh still finer and feebly comminuted, the scutellar long, 

 free or not; intervals flat; tarsi long and slender. Length (9 ) 8.5 

 mm.; width 3.5 mm. Colorado (Boulder Co.) ebenina n. sp. 



Body smaller, much less convex, the upper surface more polished and 

 usually with metallic lustre 32 



32 Elytral striae impunctate, the feebler seventh often comminuted, or 

 quasi-punctulate, however 33 



Elytral striae minutely and feebly, always more or less irregularly punc- 

 tulate 34 



33 Strial intervals evidently convex, at least in the male. Body oblong- 

 suboval, moderately convex, highly polished and with bright sub- 

 cupreous lustre on the elytra, the sides of the latter and the anterior 

 parts more greenish-aeneous; under surface deep black, the legs 

 blackish-piceous throughout, the hind tarsi (d 71 ) very long and slen- 

 der; head half as wide as the prothorax, with rather prominent eyes 

 and irregularly, subangularly impressed strides; antennae slender, 

 extending about to the thoracic base, black, the two basal joints 

 rufous, clouded above with piceous; prothorax less than one-half 

 wider than long, the sides becoming subparallel and less arcuate 

 basally; apex deeply sinuate, nearly three-fourths as wide as the 



