ii6 Bryant Walker 



Physa wiiite;i Lea. 



Physa zvhitei Lea, Pr. A. N. S. P., 1864, p. 114; Jour. A. N. S. P., VI, 1866, 



p. 172, pi. 24, fig. 96; Obs., XI, 1866, p. 128, pi. 24, fig. 96. 

 Type locality: Walker Co., Ga. ; Verdigris River, Kans. 

 Is forsJicyi according to Crandall (27, p. 69). 



PriYSA woLFiANA Lea. 



Physa wolfiana Lea, Pr. A. N. S. P., 1869, p. 125; Jour. A. N. S. P., VlII, 



1874, p. 63, pi. 21, fig. 20; Obs., XIII, 1874, p. 67, pi. 21, fig. 20. 

 Type locality : Hot Springs, Colo. 



Genus APLEXA Fleming, 1822. 

 Api,exa hordacea (Lea). 



Physa hordacea Lea, Pr. A. N. S. P., 1864, p. 116; Jour. A. N. S. P., VI, 

 1866, p. 176, pi. 24, fig. 102; Obs., XI, 1866, p. 132, pi. 24, fig. 102. 

 Type locality : Vancouver Island, Oregon. 



Referred to Aplexa by Trj^on (132, p. 170), and doubtfully by Dall 

 (32, p. 113), but its generic' position still remains to be definitely settled by 

 an examination of the animal. Dall (1. c.) states that the types came from 

 Vancouver, Wash, and not from Vancouver Island, B. C. 



Is a variety of P. venusta Lea according to Cooper (25, p. 97). 



Aplexa hypnorum L. 



Clessin (20, p. 287) distinguishes the American form {P. clongata Say) 

 on the ground that the European form has a more slender shell and never 

 a short spire as is the case with both the American varieties recognized by 

 him, but the concensus of opinion is against him. 



AplExa hypnorum arctica (Clessin). 



Physa elongata arctica Clessin, Con. Cab., Limn^iden. 1886, p. 287, pi. 41, 



fig- 5- 

 Type locality : Hudson Bay. 



Aplexa hypnorum glabra (DeKay). 



Physa glabra DeKay, N. Y. Moll, 1843, p. 80, pi. 5, fig. 83. 

 Physa clongatina Lewis, Pr. B. S. N. H., V, 1855, pp. 122, 298. 

 Range: Conn., XT. Y., and Michigan. 



This form seems to be entitled to recognition as a well marked race. 



Aplexa hypnorum tryoni (Currier). 



BuliiiKS tryoni Currier, Am. J. of Con., Ill, 1867, p. 112, pi. 6, fig. 2. 

 Type locality : Grand Rapids, Mich. 



