AMERICAN COLEOPTERA. 277 



C. heniipterus Linn. — Piceous, oblong, feebly sbining, sparsely pubes- 

 cent, elytra with humeral spot and large irregular apical space testaceous. 

 Head sparsely punctured. Thorax one-third wider than long, narrowed at 

 apex, sides feeblj" arcuate, hind angles obtuse, base slightly sinuate each side, 

 disc with a vague impression each side near the base, surface sparsely punc- 

 tured at middle more densely near the sides. Scutellum sparsely punctate. 

 Elytra conjointly wider than long, piceous, a humeral spot and large irregular 

 apical space yellow, surface sparsely punctate. Abdomen above more finely 

 punctured than the elytra. Presternum coarsely but sparsely punctured. 

 Body coarsely and more densely punctured. Abdomen sparsely and rather 

 finely punctured. Legs pale. Length .16 inch; 4 mm. 



In additioa to the anal segment the males have the middle tibiae 

 stouter than in the female. 



This species which is widely distributed over the region east of the 

 Rocky Mountains, is very constant in its system of coloration, and 

 by this may be known from any other in our fauna. It is nearly a 

 cosmopolitan species. 



C pallipeunis Say. — Form moderately robust, oblong oval, color varia- 

 ble, sparsely pubescent. Head coarsely not densely punctured. Thorax convex, 

 one-third wider than long, narrowed in front, sides moderately arcuate, hind 

 angles broadly arcuate, surface moderately densely punctured. Scutellum 

 moderately densely punctured. Elytra conjointly a little wider than long, 

 surface very regularly and moderately densely punctured. Abdomen above 

 more finely and sparsely punctulate. Prosternum nearly smooth, body coarsely 

 not densely punctured, abdomen more finely and sparsely punctured. Length 

 .12 — .16 inch; .3 — 4 mm. 



The sexual characters are as in liemipterus^ the middle tibiae being 

 even more dilated in the male. 



The variations in color are so marked in this species as to have 

 caused some synonymy. The most notable varieties will be men- 

 tioned. 



pallipennis Say. — Piceous, abdomen beneath, legs and elytra yellovv-testa- 

 ceous. Immature specimens occur entirely yellow. 



floralis Er. — Piceous, legs somewhat paler. 



. — Ferruginous brown, head and thorax somewhat darker. 



Intermediate variations between these occur so that there is no lack 

 of intermediate forms. 



Occurs west of the Mississippi River from Kansas to Texas, thence 

 westward through Arizona into the Peninsula of California, and 

 southward through Mexico. It is abundant in the flowers of Cactus 

 in the Spring. 



C diniidiatus Fab.— Oblong, color variable from piceous to ferruginous, 

 very feebly shining, sparsely pubescent. Head moderately densely punctured. 

 Thorax quadrate a little wider than long, sides nearly straight, hind angles 

 obtuse not prominent, surface coarsely and moderately densely punctured, less 



