54 CALIFORNIA ACADEMY OF SCIENCES. 



San Diego; not common: obsoletus, San Diego (Le Conte); 

 lecontei, rather common, various localities. The follow- 

 ing species are found farther north: inter sectvs, brevicol- 

 lis, confertus, strigulosiis, tristis (Lake Tahoe), xuturalis, 

 erichsoni. 



Rhantus. R. bmotatus, common generally: anisony- 

 chus, much rarer, Pomona: jtavogriseus and sinuatus are 

 reported from the State, but I have not seen specimens 

 from the south. 



Colymbetes. C. strigatus, rare; a single specimen 

 taken at San Bernardino in April: sculptilis is recorded 

 from the State by Crotch: seminiger occurs in the north- 

 east. 



Eretes. E. sticticus is a cosmopolitan species which 

 has occurred once at Soldiers' Home (Van Dyke). 



Hydaticus. H. ntagnalis is recorded from "Cal." 

 (Horn, " The Coleoptera of Baja California"*). 



Dytiscus. D. marginicotti8,8C&YCQ; several specimens 

 taken by Mr. Daggett in Bear Valley, elevation 7,000 

 feet, June; one example taken by myself at Santa 

 Monica. 



Thermonectes. T. basilaris var. intennedius, one 

 example, Pomona, September: marmoratus, near San 

 Diego (Fuchs). 



Cybister. 0. explanatus, not rare, many localities: 

 ellipticusy Colorado River. Both species are frequently 

 attracted by electric lights. 



GYRINID^. 



This family is very poorly represented in Southern 

 California. 



*Proc. Cal. Acad. Sci., 2nd Ser., Vol. IV, 1894, p. 314. 



