102 FAMIXT II. CAEABID3!. 



XXVI. Amaba Bon. ]-13. (Gr.. "to shine.") 



Black, brownish or bronzed beetles of medium size, possessing 

 the characters of the tribe Pterostichini as previotisly given. Form 

 usually oval or oblong, convex; last joint of labial palpi shorter 

 than the next to last, the latter with several setie in front : thorax 

 usually -wider than long and in most species as wide at base a« 

 elytra, the latter without dorsal punctures, ^lales with the first 

 three .joints of the front tarsi dilated, with two rows of scales be- 

 neath. 



The genus is a large one and the species very difficult to sep- 

 arate by a table or key unless both sexes are present. Even then 

 a number of the species resemble one another so closely as to be 

 only doubtfully placed. Its members are, according to Dr. Forbes, 

 mainly vegetable feeders, though one of the larger ones, obesa, is 

 known to feed largely upon the eggs of locusts or grasshoppers. 

 They occur mostly in inoist situations, beneath logs, stones, etc.. 

 and several species are known to hibernate as imagoes. 



The following are the principal papers on the Xorth American 

 species : 



LeConte. — "Notes on the A marge of the United States," in Proc. 

 Phil. Acad. Nat. Sci.. YII. 1-^55. 346. 



Horn. — "Synoptic Tables." in Trans. Amer. Entom. Soc, V. 

 1874, 127. 



Horn. — "A Study of Amara," in Trans. Amer. Ent. Soc, XIX. 

 1892, 19. ' 



Wickham.~In Joum. N. Y. Ent. Soc. IV. 1^96. 33. 



Hay ward. — "Studies in Amara." in Trans. Amer. Ent. Soc. 

 XXXrV. 1908, 13-66. 



About 70 species are known from the United States. Of these 

 19 have been taken in Indiana, while two or three others probably 

 occur. For convenience the Indiana species are separated into 

 three groups, and these in turn iato species. 



KEY TO GEOtPS OF INDIANA AMABA. 



a. Thorax distinctly broader in front > 'f than at the base, and usnally more 

 or less cordiform. Group A. 



aa. Thorax broadest at base, thence gradually narrowed to apex. 



6. Hind tibiie pubescent on the inner side in the males. Group B. 



66. Hind tlbire net distinctly pubescent on the inner side in the males. 



Group C. 

 Gbotjp a. 



But five species, whose known range is such as to probably in- 

 clude Indiana, belong to this group. With one exception they are 



