THE WATER SCAVENGEE BEETLES. 



261 



tember 7. A member of the boreal fauna. Next in size to ductus, 

 but brownish instead of black, more oblong and less convex. 



P. dijfusus Lee, is recorded from Illinois and westward. 



508 *(1633). Philhydrus cinctus Say, Long's Exped., II, 1824, 276; ibid. 

 1,182. 



Oval, slightly oblong, very convex. Black, shining ; entire margin dark 

 reddish-brown. Thorax with basal marginal line very fine and indistinct; 

 its surface finely and evenly punctured. Elytra a little more coarsely and 

 sparsely punctured than thorax, the dorsal rows distinct but feebly im- 

 pressed. Length 6.5-7 mm. 



Throughout the State; common. Hibernates as imago. Febru- 

 ary 11-December 8. 



507 (1636). Philhydrus pekplexus Lee, Proc. Phil. Acad. Nat. Sci., VII, 



1855, 371. 



Oblong-oval, fully twice as long as wide. Above piceous-black, shining ; 

 sides of thorax and elytra with narrow paler border. Thorax closely and 

 finely punctate, its basal marginal line always distinct. Elytral punctures 

 coarser than those of thorax, the usual dorsal rows feebly indicated. Length 

 4—5.5 mm. 



Common throughout the northern half of State; less so in the 

 southern portion. April 23-October 23. 



XII. Helochares Muls. 1844. (Gr., " marsh + rejoice. ") 



Very close to Philhydrus and formerly united with it. One spe- 

 cies occurs in Indiana. 



508 (1639). Helochares macultcollis Muls., Ann. Sc. Phys. Nat. Lyon., 



VII, 379. 



Oblong-oval, distinctly narrowed in front, subdepressed. Above dull 

 brownish-yellow ; occiput and discal spot of thorax piceous ; under surface 

 black or piceous. Elytra with ten rather deeply impressed rows of serrate 

 punctures; intervals flat, finely punctulate, the fifth and ninth with a row 

 of coarse punctures. Length 4-5.5 mm. 



Lawrence and Dubois counties ; scarce. May 9-August 5. 



XIII. Cymbiodyta Bedel. 1881. (Gr., "boat + dive. ") 



Small, oval, piceous or brownish species, formerly included un- 

 der both Philhydrus and Hydrocombus, but having only four joints 

 on the middle and hind tarsi. In the species occurring in the East- 

 ern United States the elytra are not striate, but usually have sev- 

 eral rows of coarse punctures. One species has been taken in the 

 State, while two others may occur, 



