58 GEO. H. HORN, M. D. 



not closely placed, not more dense near the sides. Elytra as wide as the thorax, 

 humeri obtuse, sides feebly arcuate posteriorly, disc moderately deeply striate, 

 strife crenately punctured, intervals moderately convex, indistinctly sparsely 

 punctate. Mesosternum opaque and alutaceous, rugose at the sides, not carinate. 

 Metasternum at sides opaque, indistinctly punctate. Abdomen alutaceous, 

 coarsely indistinctly punctate. Anterior tibia", smooth in front, tridentate exter- 

 nally and distinctly crenate above, the first tarsal joint shorter than the second. 

 Posterior femora sparsely punctate, a row of coarsse punctures distantly placed 

 extending the entire length of femur, the firet tareal joint nearly as long as the 

 next three. Length .20 inch ; 5 mm. 



Male. — Head sparsely punctate, the punctures a little closer, not coarser, near 

 the sides and front. Anterior tibial spur stout, curved near the tip. 



Female. — Head more coarsely punctate, much more densely and coarsely at 

 sides and front. Anterior tibial spur slender and acute. 



The elytra in this species are of the same pale yellow color as seen 

 in the paler parts oi prodromus. The scutellum and sutural interval 

 are piceous, the interval being extremely narrow as it approaches 

 the apex. The pubescence of the elytra is very fine and easily 

 abraded, but the facies of the species is so nearly that of femomUs or 

 prodromus, that tliei'e will be no difficulty in recognizing its relation- 

 ship. 



Occurs in Colorado and Nebraska. 



A. Walsllii Horn. — Moderately elongate, slightly broader posteriorly, body 

 beneath brown, head and thorax piceous-black, the latter with broadly yellow 

 sides, elytra fuscous less shining, the base and sides dull yellow, legs yellow. An- 

 tennae testaceous, club darker, palpi pale. Head moderately convex, without 

 trace of tubercles, very sparsely and finely punctate in both sexes. Clypeus 

 broadly feebly emarginate in front, the angles broadly rounded, slightly retlexed, 

 sides oblique, genaj scarcely at all prominent. Thorax less than twice as wide as 

 long, slightly narrowed in front, sides moderately arcuate, the margin fimbriate, 

 hind angles rounded, base arcuate with very fine marginal line ; disc moderately 

 convex, very finely and sparsely iiunctate, a few coarse punctures near the sides. 

 Elytra as wide at base as the thorax, humeri ol)tuse, sides feebly arcuate, moder- 

 ately deeply striate, striae very finely punctured, intervals convex, alutaceous 

 with few extremely fine punctures, the three outer intervals more distinctly 

 punctate ; elytral margin fimbriate with moderately long hairs. Mesosternum 

 finely alutaceous, a smoother space at middle. Metasternum alutaceous with 

 very few scattered puuctures. Abdomen sparsely punctate, alutaceous, sparsely 

 hairy. Anterior tibise smooth in front, externally bidentate, the upper tooth 

 wanting in '^ , or very feeble 9 , not crenate above, the first joint of the tarsi as 

 long as the second, joints 2-3-4 scarcely longer than wide. Posterior femora 

 alutaceous, with very few puuctures, the first tarsal joint as long as the next 

 three. Length .20-.24 inch ; 5-6 mm. 



Male. — Anterior tibia sinuate on the inner side and fimbriate, a distinct emar- 

 gination opposite the second tooth, spur moderately stout, suddenly flexed at tip. 

 Metasternum deeply sulcate. Posterior femora with a dentiform process from 

 the middle of the posterior margin, sometimes very feel)le. 



