94 BIOLOGICAL SURVEY OF 



Agabus Leaeli 



A. GAGATEs Aiibe. S. W. Harbor; Bar Harbor, June 25- 

 July 11. 



Illybius Erichson 



I. suBAENEus Er. S. W. Harbor; Bar Harbor, July 14-29. 



I. ANGUSTiOR Gyll. S. W. Harbor, July 14. 



I. BiGUTTULUs Germ. Salisbury Cove, Aug. 10. 



COPTOTOMUS Say 



C. iNTERROGATus Fab. Bar Harbor ; Salisbury Cove, June 11- 

 Aug. 10. 



CoLYMBETES CLiirville 



C. scuLPTiLis Harr. Bar Harbor, June 9-13. 



Dytiscus Linnaeus 



D. DAURicus Gebl. Ironbound Isl. (Blaney). 



D. sp.? Bar Harbor, July. Larva from lily pond, Mt. Desert 

 Nurseries. It may possibly represent the above species. 

 The larvae of this genus are popularly known as "water 

 tigers." 



AciLius Leach 



A. sEMisuLCATus Aubc. Small pond on hill east of Salisbury 

 Cove, Aug. 10, 1926. 



Gyrinidae. Whirligig-beetles 

 DiNEUTES MacLeay 



D. HORNi Robts. Ice ponds, Manset ; Bar Harbor, July 15-26. 



Gyrinus Geoffroy 



G. BOREALis var. LUGENS LcC. Ice ponds, Manset; Bar Har- 

 bor, July 15-Aug. 14. 



G. puGioNis Fall. Bar Harbor; Salisbury Cove, July 29- 

 Aug. 10. 



Hydrophilidae. Water-scavenger beetles 

 Hydrophilus De Geer 



H. oBTusATus Say. Bar Harbor, July 24. 



Tropisternus Solier 



T. GLABER Hbst. Witch Hole Pond ; Salisbury Cove, June 13- 

 Aug. 10. 



