104 GEOLOGICAL SURVEY OF NEW JERSEY. 



HYDATICUS, Leach. 

 H. piceus, Lee. 



Very rare, one specimen only ; Caldwell — Crane. 



H. bimarginatus, Say. 



Anglesea, rare — Liebeck. 



DYTISCUS, Linn. 

 D. harrisii, Kirby. 



Caldwell, common — Crane. 



D. fasciventris, Say. 



Camden, Gloucester and Atlantic counties — Wenzel. Cald- 

 well, rare — Crane. New Jersey — Collection Roberts and United 

 States National Museum. Madison. 



D. hybridus, Aube. 



New Jersey — Collection Roberts and United States National 

 Museum. 



D. verticalis, Say. 



New Jersey — Collection United States National Museum. 

 Madison. 



ACILIUS, Leach. 

 A. semisulcatus, Aube. 



Caldwell, common — Crane. Newark. New Jersey — Collec- 

 tion United States National Museum. 



A. fraternus, Harr. 



Anglesea, rare — Liebeck, New Jersey — Collection Roberts 

 and United States National Museum. Madison, 



A. mediatus, Say. 



Sea-shore, rare — Liebeck. Camden, Gloucester and Atlantic 

 counties — Wenzel, New Jersey — Collection Roberts and United 

 States National Museum. Fort Lee, abundant — Linell. 



THBRMONBCTBS, Esch. 

 T. basilaris, Harr. 



Generally distributed, moderately abundant — Liebeck. New 

 Jersey — Collection Roberts and United States National Museum. 



