120 



FAMILY II, C A.EABLTW.. 



XXXI. Calathus Bod. 1813. (NL., "a circular basket" or 



"calyx-like.") 



Brownish or black beetles of medium or small size, possessing 

 the characters of the tribe Platynim. From allied genera they are 

 separated by the smooth tarsi, the claws of which are serrate. Six 

 examples of our most common species (gregarius) were dissected 

 by Dr. Forbes, who found that two-thirds of their food consisted 

 of caterpillars and other insect larva?, and the remainder of the 

 pollen of grasses. Our species occur beneath logs, etc., usually in 

 dry upland woods. They are difficult to separate, and the only 

 papers treating of them are by 



LeConte.—In Proc. Phil. Acad. Nat. Sci., VII, 1854, 36; 1860, 

 317. 



Ten species have been described from the United States, three 

 of which have been taken in Indiana. 



KEY TO INDIANA SPECIES OF CALATHUS. 



a. Thorax not narrowed behind, its base as wide as base of elytra ; basal 

 impressions feeble or wanting. ; 

 b. Entire upper surface polished, shining; sides of thorax moderately 

 reflexed. 194. gregakitjs. 



bb. Head and thorax shining, elytra dull, opaque; sides of thorax de- 

 pressed, broader behind, not retlexed. 195. opaculits. 

 aa. Thorax broadest rather before the middle, slightly narrowed toward 

 the base, the latter narrower than base of elytra ; basal impressions 

 distinct. 196. impunctatus. 



*194 (742). Calathus gregarius Say, Trans. Amer. Phil. Soc, II, 1823. 

 47 ; ibid. II, 472. 



Elongate-oval. Dark chestnut or reddish-brown, the margins of thorax 

 paler ; antenna and legs reddish-brown. Thorax slightly longer than broad, 

 hind angles rounded. Elytral striae shallow, not punctured. Length 10-11 mm. 



Throughout the State ; common. January 11-November 17. Gre- 

 garious in cold weather. 



*195 (744). Calathus opaculus Lee, Proc. Phil. 



Acad. Nat. Sci., VII, 1854, 37. 

 Form of gregarius. Head and thorax reddish - 

 ( >r chestnut-brown ; antennae and legs paler ; elytra 

 'lull piceous or very dark brown. Thorax not 

 longer than wide, slightly narrowed toward apex. 

 Elytra minutely alutaceous, the striae very fine. 

 Length 8.5-10 mm. (Fig. 71.) 



Lake^ Marion, Putnam and Vigo counties; 

 frequent. January 1-November 24. Prob- 

 Fig. 7i. x 3. (Original.) ably occurs throughout the State, 



