Cogswell 1950 Cinclus mexicanus 2 July 29 Sugar Bowl Cr., 6900 ft. 1.2 mi. 55W Donner Pass, Placer Co. Calif. - I immature at the "swimming" pool, using the small raft built by our boys as a perch from which to peer under water; but I did not see it go under. None seem to be found along this snow-fed stream early in the summer (due to lack of aquatic organisms suitable as food ?). Aug. 8 I seen in this same spot at dusk. Aug. 11 " " " " Aug. 10 mouth of Castle Cr., 6760 ft. at I. Van Norden, Nevada Co. Calif. - I on boulders dotting the sloping mud shores of the lake shore & just up the small stream. Aug. 17 Hampshire Rocks, 5900 ft., on S. Fork Yuba R., Placer Co, Calif. - I flushed from large boulder, in mid- stream in deep water portion on this solid granite stream bed area.