276 NORTH AMERICAN FAUNA. lNo.7. 



Physa gyrina Say. 



Hot Springs, Panamint Valley, California (Mus. No. 123(507), April 22, 1891; also 

 Pahranagat Valley, Nevada (Mus. No. 123608), May 25, L891; Daggett, 

 Mohave Desert, California, March 31, 1891 (Mus. No. 123914), Dr. C. Hart 

 Merriam. Garlick Springs, San Bernardino County, Cal. (Mus. No. 123609), 

 March 14, 1891; Resting Springs, Inyo County, February 9, 1891 (Mus. No. 

 123916) ; Keeler, Inyo County, Calif. (Mus. No. 123610), Juno 1, 1891 ; Gorman 

 Station, 8 miles south of Fort Tejon, Cal., July 2, 1891 (Mus. No. 123011), 

 T. S. Palmer. Kern River, California (Mus. No. 123012), and Fairfield, 

 Utah (Mus. No. 123613), June 25, 1890, Vernon Bailey. Hidalgo, Tamaulipas, 

 Mexico (Mus. No. 123614); Monterey, Mexico (Mus. No. 123915), William 

 Lloyd. 



Dr. Merriam's Hot Springs examines of the above are fine large 

 dark- colored shells; they vary considerably in elevation of spire. In 

 the shorter spired individuals there is a tendency to tabulation or flat- 

 tening of the upper part of the body whorl, following the suture, sug- 

 gesting the shouldered aspect of Physa humerosa, a common form on the 

 surface of the Colorado Desert. His Pahranagat Yalley lot are paler 

 and more elongated, with a higher and more acute spire, suggestive of 

 P. hypnorum. 



Palmer's Garlick Springs shells are nearer the typical form; taken as 

 a whole, in size, color, and general facies; some of them hint of Tryon's 

 species diapliana, a local varietal aspect of gyrina, found in the neigh- 

 borhood of San Francisco Bay. His Keeler: examples, from the shores 

 of Owens Lake, are few in number; two of these are over rather than 

 of the usual size, and two are hardly adult; all are characteristic, form 

 considered. The Gorman Station lot, of which there is a large number, 

 also collected by Palmer, at a point 8 miles south of Fort Tejon, are 

 exceedingly uniform iu size, color, and proportions; they are all adults, 

 of medium size, rather slenderer on the whole than the typical form, 

 but not as slender as Merriam's Pahranagat examples. Bailey's five 

 specimens from the South Fork of Kern Eiver, at an elevation of 

 2,700 feet, are apparently adults of a dwarfed form, less than half the 

 size of average typical adults; his Fairfield specimens were found in a 

 spring. At the first Mexican locality Mr. Lloyd found a single indi- 

 vidual; at Monterey, seven specimens; these latter exhibit the modifi- 

 cations in texture, solidity, etc., which so frequently characterize north- 

 erly forms of this and allied groups, where the distribution extends into 

 southerly or warmer regions. 



Physa heterostropha Say. 



Bennett Spring, Meadow Valley, Nevada (Mns. No. 123616), Dr. C. Hart Merriam, 



May 20, 1891. Owens Valley, Inyo Couuty, Calif. (Mus. No. 123617), F. 



Stephens, July 7, 1891. Hot Springs, Panamint Valley, California (Mus. 



No. 123618), Vernon Bailey, January 9, 1891. Brownsville, Tex. (Mus. No. 



123619), William Lloyd. 



Dr. Merriam's Bennett Spring shells were found by him at a point 

 7 miles west of Meadow Creek, at an elevation of 6,000 feet; they 

 range from adolescent to mature, the largest being rather under than 



