150 GEO. H. HORN, M. D. 



Thorax widely margined, the margin more or less translucent. 

 Interstrial spaces with confused punctures. 



Head and thorax similar in color to the elytra, the latter without distinct 

 humeral and lateral paler spaces. 

 Margin of thorax of moderate extent, very little reflexed and scarcely 

 translucent, with many, usually three or more, setigerous punc- 

 tures laticollis Say. 



Margin of thorax wide, translucent, distinctly reflexed, with one or two 



setigerous punctures cribricollis Dej. 



Head and thorax usually paler than the elytra, the latter with distinct 

 humeral spot and lateral margin paler, the surface in fully colored 



specimens somewhat metallic, |)laiii|>emiis Lee. 



Interstrial spaces with a single row of punctures clcgans Lee. 



Thorax .arrowly margined. 



Thorax distinctly broader than long, the margin wider than in the follow- 

 ing species and with but one setigerous puncture at the side. 



ii ui color Kbv. 

 Thorax not wider than long, margin extremely narrow, sides with at least 

 two setfe. 

 Elytra rather flat, intervals densely and comparatively finely punctured and 



without lustre americana Dej. 



Elytra normally convex, intervals not densely punctured, the punctures often 

 coarse, surface shining. 

 Thorax ecpially punctured, the median line feebly impressed. 



Thorax very coarsely punctured, the punctures subcontinent at the sides, 



margin rarely with translucent edge ci'ibratu . L< <•. 



Thorax normally not confluently punctured, sides with distinct but 

 narrow translucent border. 

 Surface conspicuously pubescent, elytra never with humeral pale space. 



pilosa Say. 

 Surface not conspicuously pubescent, elytra with pale humeral space. 



borealis Lee. 

 Thorax unequally punctured, median line deeply impressed. Elytral inter- 

 vals with one row of punctures neglecta Hald. 



C. laticollis Say. — Piceous, moderately shining, elytra often with faint 

 bluish tinge, legs and antennae rufo-testaceous. Head coarsely and deeply, not 

 densely punctured, middle of front less so. Thorax about one-third wider than 

 long, sides arcuate, slightly sinuate posteriorly, hind angles distinct, not promi- 

 nent, margin moderate in width, nearly equal from apex to base and slightly 

 reflexed, disc moderately convex, median line distinct but not entire, surface 

 coarsely and deeply punctured, rather sparsely at middle, more densely at the 

 sides and base, with moderately long erect brownish hairs, the margin with usually 

 four punctures hearing longer erect setse. Elytra oval, uniformly piceous, with 

 semi-erect brownish hairs, those on intervals 3 — 5 — 7 longer, surface rather deeply 

 striate, strige with coarse punctures, intervals slightly convex, very irregularly 

 biseriately punctulate. Protho'rax beneath coarsely and deeply punctate, body 

 and abdomen very sparsely punctate. Length .44 — .4S inch; 11 — 12 mm. 



Male. — Anterior tarsi with three joints moderately dilated and biseriately 

 squammuligerous. Anal segment slightly einarginate, trisetose each side. 



Female. — Tarsi slender. Anal segment entire, trisetose each side. 



