THE MOUNT DESERT REGION 97 



HALiPLroAE. The Crawling Water Beetles 



They live around the margins of brooks and ponds where 

 they crawl over the aquatic plants that lie flat on the water. 

 Best taken by raking vegetation onto a screen and looking- 

 for them as the material dries. 



Haliplus Latreille 



H. RUFicoLLis DeG. (2318). All in the genus live in shallow 

 pools where they may be taken crawling on aquatic plants. 

 Ireson Hill Pd., Sept.^ 30; New Mill Pd., Aug. 7. 



Dytiscidae. The Diving: Beetles 



These predaceous ones live in pools and the most sure way 

 to take large ones is to suspend a minnow trap baited with a 

 piece of fish. The opening of the trap should not be too large. 

 Scraping the edges of pools will get the others. 



Laccophilus Leach 



L. MAcuLOSus (Germ.) (2351). This 'pool loving' species, as 

 its name indicates, is commonly found in the smaller pools 

 on the Island. It is the first of the family to appear in the 

 spring, and remains until cold weather, when it probably 

 hibernates. 



CoELAMBUS Tliomsoii 



C. iNAEQUALis (Fab.) (2403). Pare, having been taken but 

 once. Three specimens at station F186, Sept. 1, '34. 



Hydroporus Clairville 



H. UNDULATus Say (2447). Ireson Hill Pd., July 12. Pond 

 near N. E. Branch. Sept. 1 scraping aquatic plants. 



H. NIGER Say (2514). New Mill Pond, Aug. 7; S. W. Harbor, 

 July 14. Scarce. 



H. STEIOLA Gyll. New Mill Pd., Aug. 7. Scarce. 



H. sp. One individual taken New Mill Pond, Aug. 7, '34. 



