70 GEO. H. HORN, M. D. 



The tabular separation based on the above with other less important 

 characters is given below, the numbers indicating a cabinet arrange- 

 ment based on superficial resemblances. 



Hind angles of thorax not carinate, basal margin without incisure. Flanks 



\ beneath sparsely punctured il. bilobatlis. 



Hind angles carinate, basal incisures more or less distinct 2. 



2. — Flanks of thorax beneath with a large smooth space j)osteriorly or very 



much less densely punctured .S. 



Flanks of thorax beneath without smooth space, at most^ very little less 



densely punctured posteriorly 4. 



3. — Carina of hind angles fine and close to the margin, incisures feeble. 



Black, elytra luleous 6. oregonus. 



Ferruginous brown, elongate 7. so^cifer. 



Carina well marked and divergent from margin, incisures well marked. 

 Hind angles divergent. Prosternal mucro horizontal. ..9. decoloratus. 

 Hind angles not divergent. Mucro flexed. 



Third joint of antennse shorter than the fourth, thorax very sparsely 



and indistinctly punctured 8. jndistiuetiis. 



Third joint of antennse equal to the fourth, thorax variably but always 



very distinctly punctured 10. niemnoiiius. 



4. — Prosternal mucro horizontal, the mesosternum with its lobes moderately 

 prominent. 

 Thorax sparsely punctured at middle and but moderately densely punc- 

 tured at the sides, hind angles not divergent 3. morio. 



Thorax closely punctured at middle and very densely at the sides. 

 Pubescence very short and black. Hind angles somewhat divergent. 



4. dilaticollis. 

 Pubescence longer, brownish. Hind angles not diveigent. 



5. tiimescens. 

 Prosternal mucro flexed, the mesosternum oblique its lobes not at all 

 prominent. 



Thorax very convex, pubescence long, black, erect 1. tiirtllS. 



Thorax moderately convex, pubescence very short 2. carbonatus. 



The notes which follow are intended to be supplementary to the 

 fuller descriptions already given by Drs. Leconte and Candeze, they 

 are however ample for the separation of the species known to us 

 at present. 



The synonymy given under memnonius, detolorafus and bilohatui^, 

 may be surprising to some students and cause doubts in the minds 

 of others, to both classes I can say that the conjoined material in 

 my own and Dr. Leconte's cabinet is abundant enough to sustain the 

 views here given. 



A. hirtus Cand. — Rather slender, black, moderately shining, sparsely 

 clothed with moderately long and more or less erect black hair. Thorax more 

 convex than usual, very coarsely and moderately densely punctured, hind 

 angles carinate and divergent; flanks beneath coarsely and moderately densely 



