I880.J 169 [Horn. 



The species are as follows : 



Clypeus on each side with one setigerous punctnre. 

 Surface opaque, elytra feebly striate, especially at tip. 



Hind angles of thorax obtuse, sides regularly arcuate, base as wide as 



the elytra 13. furvus Lee. 



Hind angles of thorax sharply rectangular, sides of thorax slightly ar- 

 cuate posteriorly, base narrower than the elytra (Pacific coast 

 species). 

 Intercoxal process and middle of second abdominal segment punc- 

 tured, punctures with short setae. Metasternum in front and 

 behind punctured. 

 Thorax feebly narrowed posteriorly, basal impressions very 



feeble, surface entirely punctured 14. semipunctatus Lee. 



Intercoxal process and metasternum smooth. 



Thorax with broad but very shallow basal impressions. Elytra 



broad, sides distinctly arcuate 15. consobrinus Lee. 



Thorax with rather deep linear impressions. Elytra nearly paral- 

 lel 16. californicus Dej. 



Surface shining in both sexes, elytra more deeply striate. 



Elytral intervals feebly convex, quite distinctly but sparsely punctu- 

 late, elytra oblong, sides nearly parallel, surface feebly shining. 



17. interpunctatus Khj. 

 Elytral intervals convex, smooth, elytra oval, sides arcuate, surface 



shining ; form more robust 18. agricola Say. 



Clypeus on each side with two setigerous punctures. 

 Hind angles of thorax obtuse. 

 Side margin of thorax very distinctly depressed and with the base 



punctulate 19. Harrisii Lee, 



Side margin of thorax scarcely depressed 20. nigerrimus Dej. 



Hind angles of thorax distinct, nearly rectangular. 

 Elytral intervals distinctly but sparsely punctulate, sides of elytra 



nearly straight, subparallel 21. nigrita Dej . 



Elytral intervals smooth, shining, sides of elytra distinctly arcuate, 

 form more robust 22. melanopus Hald. 



To this group belongs A. signatus Illig., of Europe and Asia. It resem- 

 bles semipunctatus Lee, and has but one setigerous puncture on each side 

 of the clypeus. The intercoxal process is smooth. It differs from an}^ of 

 the species of the group bj^ the first joint of the middle tarsus of the male 

 having no pubescence beneath. 



13. A furvus Lee. Oblong oval, black, opaque. Clypeus with one 

 setigerous puncture each side. Thorax very little wider at base than at 

 apex, sides feebly arcuate, hind angles obtuse, side margin feebly depressed, 

 surface smooth at middle, finely punctured at base and sides. Elj^tra finely 

 striate, intervals flat, dorsal puncture normal, surface opaque, more so in $. 

 Body beneath smooth, shining. Length .44 — .50 inch ; 11 — 12.5 mm. 



PROC. AMER. PHILOS. SOC. XTX. 107. V. PRINTED KOVEMBEU 27, 1880. 



