THE GROUND BEETLES. 67 



Tribe IV. BEMBIDIIN1. 



Beetles of small size, black, reddish-brown or bronzed in hue, 

 having the antennae slender, arising from beneath a slight frontal 

 margin, the first or the first two joints glabrous; mandibles feebly 

 curved, acute at tip ; last joint of palpi awl-shaped, the next to last 

 club-shaped and with two set;*?. Thorax with a bristle-bearing 

 puncture at the side and another at hind angle; prosternum not 

 prolonged. Elytra with sides narrowly inflexed, margin inter- 

 rupted behind the middle, the disk with dorsal punctures ; surface 

 in our genera glabrous. 



The tribe is represented in the United States by four genera, 

 three of which occur in Indiana. 



KEY TO INDIANA GENERA OF BEMBIDIINI. 



(i. Front tibise not obliquely truncate at apex; sutural striae of elytra not 



recurved at apex ; scutellar striae present. 



1). Eyes large or moderate. XVII. BEMBIDIUM. 



66. Eyes entirely wanting. XVIII. ANILLUS. 



(id. Front tibiie obliquely truncate at apex ; sutural striae recurved at apex ; 



scutellar striae absent. XIX. TACHYS. 



XVII. BEMBIDIUM Latr. 1832. (Gr., "a buzzing insect + little. ") 



A large genus of small black, greenish, or bronzed beetles, hav- 

 ing the characters of the tribe as above given. Elytra glabrous, 

 striate; front tibiae.- deeply emarginate, apical angle not obliquely 

 truncate; hind COXEO touching. Males with the first two joints of 

 front tarsi dilated, the first joint being slightly elongate and nearly 

 quadrate, the second more or less triangular, with the inner angle 

 usually slightly prolonged. 



The Bembidids occur for the most part along the banks of 

 streams, ponds and lakes, especially on mud flats and bars. A few 

 are found in moss and amongst old leaves about the trunks of 

 trees and stumps or beneath the bark of logs. Several, perhaps 

 most, of the species hibernate as imagoes. 



The principal papers treating of the genus are as follows : 



Leconte. "Catalogue of the Species of Bembidium found in 



the United States" in Proc. Phil, Acad. Nat. Sci., 1857 ; 2. 

 Hay ward, Roland.- "On the Species of Bembidium of America 



North of Mexico" in Trans. Amer. Ent. Soc., XXIV, 1897. 



32-143. 

 Hayward, Roland. "Synonymical Notes on Bembidium and 



Descriptions of New Species" in Trans. Amer. Ent. Soc., 



XXVII, 1901, 156-158. 



