Typical G. angulata and its ssp. haroldiana occupy the 

 same geographic area, both burrow into clay hanks or bottoms 

 of streams, but angulata is found only in rapid streams, whereas 

 haroldiana should be looked for in sluggish waters (but not 

 lakes). Both may be expected to turn up at various points in 

 southern California when intelligently soughl for. 



Confined to the streams flowing into the Pacific Ocean, 

 from the Praser Valley, British Columbia, to southern Califor- 

 nia. 



Los Angeles System : Los Angeles River (R. E. C. Stearns) 

 fide Dall. 

 Gonidea angulata haroldiana Dall. Pig. IV. 



Anodonta angulata var. subangulata Hemphill, Zoe, I, 

 1891, 325, PL X. 1-2; not Anodon(ta) subangulata Anthony, 

 lsii.~>: Gonidea angulata var. haroldiana Dall, Smith. Misc. Coll. 

 L. 1908, 4!)!). 



The specimen figured is one of the cotypes in the writer's 

 collection and is somewhat more finely developed than usual. 

 It might be noted that the original specimens of this subspecies 

 were actually obtained from the Coyote Creek between San 

 Jose and San Francisco Bay, not the Guadeloupe Creek, as re- 

 corded by Dall through a misunderstanding. Gonidea formerly 

 occurred in the latter stream but was destroyed by sewage 

 some years ago. 



To 1)]'. Tremper is due the credit of extending the range 

 of this variety to southern California. 



Los Angeles System: Chino ('reek, seven miles south-wesl 

 of Ontario. San Bernardino Valley (R. IT. Tremper.) 



SPHAERIDAE. 



Sphaerium simile (Say). 



Cyclas similis Say, Nich. Encyc. (IEd.) IT, 1817, PL I, 9; 

 C. striatina Lamarck, An. Sans. Vert. V, 1818, 560; C. dentata 

 Ealdeman, Proc. Phila. Acad. Sri., 1841, 100; C. solidula Prime. 

 Proc. Bos. Soc. Nat. Hist. IV, 1851, 158; C. nobilis Could, Proc. 

 Bos. So.-. Nat. Hist. V. 1855, 22!); :;: Sphaerium striatinum Prime. 

 .Mon. Am. Corbie. 1865, 37, fig. 29; ::: S. dentatum Hannibal. W. 

 Coasl Shells 1910, 305, PL II. 5; not S. "simile Say" Baker, 

 Chic. Moll. II, 1902, 116, PL XXVI I. 3.=S. sulcatum Lam. 



A widespread polymorphic species variously and often in- 

 curred !y identified. 



The Arizona records while near the southern limit of its 

 range are doubtless authentic. Thai from San Pedro, Califor- 

 nia, requires verification. 



North America generally south to Alabama, Arizona, and 

 middle California. 



Los Angeles System: San Pedro (T. II. Webb) i\i]^ Gould. 



