200 



FAMILY III. HAL1PLILVE. 



Throughout the State; frequent. April 19-Deeember 18. 



381 (1209). Anisodactylus sericeus Harr., N. Eug. Far., 1828, 177. 



Oblong. Black, opaque ; antennae reddish-brown ; femora piceous, tibise 

 and tarsi pale. Thorax broader than long, apex and base equal ; sides regu- 

 larly curved, hind angles rounded, basal impressions obsolete; surface 

 sparsely punctate, more densely at base and near the sides. Elytral inter- 

 vals flat, densely punctulate, each puncture bearing a short, fine hair. 

 Length 10 mm. 



Lake, Marion, Vigo and Posey counties; frequent. February 

 21-November 17. Noted on stems and burrowing beneath the roots 

 of grasses and sedges about ponds. Also taken at electric light. 



*382 (1210). Anisodactylus interstitialis Say, Trans 

 Amer. Phil. Soc, II, 1823, 57; ibid. II, 

 480. 



Form and structure of sericeus. Color as given in 

 key. Thoracic margin broader, more depressed; me- 

 dian line and basal impressions evident, the latter 

 broad and shallow. Elytral intervals subconvex, densely 

 and rather coarsely punctate. Length 9.5-10 mm. (Fig. 

 101.) 



Throughout the State; common, especially in 

 sandy regions. March 17-December 18. A half dozen just 

 emerged as imagoes were noted on November 28. 



Family III. HALIPLI DyE. 

 The Crawling Water Beetles. 



In the North American fauna this family is represented by less 

 than 30 known species of small, very convex aquatic beetles. In 

 color they are light brownish-yellow, more or less spotted with 

 black, while in form they are oval and tapering at each end. The 

 elytra bear rows of punctures- and the scutellum is invisible. 



They comprise a family intermediate between the Carabidae and 

 Dytiscidae, having the antennae glabrous, filiform, 10-jointed and 

 inserted on the front before the eyes; thorax with distinct side 

 pieces; hind coxae contiguous at middle and prolonged as broad 

 plates which conceal the basal half of hind femora and from three 

 to six of the ventral segments. The slender but clubbed hind fe- 

 mora move between these plates and the abdomen, and are not 

 adapted to vigorous swimming. 



Although aquatic in habit, these little beetles swim but feebly. 

 Where found they usually occur in numbers. They live in shallow 

 water about the margins of ponds, lakes and pools of streams, where 



