30 GEO. H. HORN, M. D. 



2. — Clypeus distinctly denticulate each side of tbe eraargination, the sides 



strongly arcuate rudis. 



Clypeus angulate each side of eraargination the sides oblique: no depression 



near hind angles of thorax phseopteriis. 



Clypeus feebly emarginate at middle, on each side broadly rounded 3. 



3. — Color piceous, the elytra in one species reddish yellow. 



Striae of elytra moderately deep, intervals convex, not punctulate; en- 

 tirely piceous brevicollis. 



Strige moderately deep, intervals convex and distinctly punctulate. 



iiiargiiiatiis. 

 Striffi fine, scarcely punctulate, intervals nearly flat, finely and densely 



punctulate; elytra reddish yellow ochreipeiiiiis. 



Color entirely rufo-ferrugiuous; surface polished, the sculpture very feeble; 

 striffi of elytra fine and very finely jnmctulate ; intervals flat and 



smooth Haldeiiiaiii. 



A. e.^plaiiatus Lee— Elongate, moderately convex, piceous shining, the 

 sides of the head, sides of thorax broadly and base narrowly, elytra and legs dull 

 rufo-te.staceous. Antennse rufo -testaceous, the club somewhat darker. Head 

 moderately convex, finely and moderately closely punctured, front feebly tritu- 

 berculate. Clypeus broadly but not deeply emarginate at middle, the angles on 

 each side prominent, subacute and slightly reflexed, the sides oblique, geuai mod- 

 erately prominent but obtuse. Thorax nearly twice as wide as long, narrower 

 in front, the sides broadly explanate and slightly reflexed, arcuate from the hind 

 angles which are very broadly rounded, base arcuate, slightly sinuate each side 

 of middle, a di-stinct but very fine marginal line ; disc moderately convex, a 

 slight median longitudinal impression near the base, the punctures moderate in 

 size, closely placed, somewhat coarser and denser near the sides. Elytra slightly 

 narrower at base than the thorax, humeri obtuse, sides slightly arcuate behind 

 the middle, disc striate, striae fiuely and closely punctured, intervals moderately 

 convex and with very numerous punctures irregularly placed. Body beneath 

 moderately finely not closely punctate. Abdomen moi"e closely and coarsely 

 punctate, sparsely pubescent. Mesosternum opaque at middle and alutaceous, at 

 sides punctate, very distinctly carinate between the coxte. Anterior tibiae smooth 

 in front, tridentate externally and obsoletely crenate above, the first tarsal joint 

 nearly as long as the second. Posterior femora sparsely punctate, a few coarse 

 punctures in line near the knee, the first tarsal joint as long as the next three. 

 Length .34 inch ; 8.5 mm. 



The only specimen seen is a female, the spur of the anterior tibia 

 is slender and acute. 



This species is remarkable for its size and style of coloration. It 

 is the only one in the present series with the sides of the piceous 

 thorax conspicuously paler in color, otherwise it resembles ochreipen- 

 nis, this being the only one for which it might be mistaken. The 

 presence of a very well elevated carina between the middle coxie is 

 a character that would not be expected in this series, and this with 

 the explanate and closely evenly punctui'ed thorax make it one of 

 the most easily to be recognized species in our fauna. 



Occxirs in Colorado, collected by Prof F. H. Snow. 



