PHYSA. 151 
29. PHYSA HETEROSTROPHA, Say. 
Hald. Monog. p. 23, t. 2, figs. 1—9. 
Physa osculans, in part, Hald., t. 2, figs. 11, 12. 
Physa plicata, DeKay. Plate 8, fig. 7. 
Mr. W. G. Binney includes also in the 
synonymy of this species P. aurea, Lea, which 
I believe to = P. Troostiana, Lea, and P. 
cylindrica, Newcomb, which I consider a syno- 
nym of P. gyrina, Say. FP. inflata, Lea, also 
placed here by Mr. Binney, is very probably 
distinct from all other species, and I have so 
treated it. In conclusion, Mr. B. includes in 
his catalogue of specimens in the Smithsonian 
Museum several lots having west-coast locali- 
ties, and none of these are really P. heterostro- 
pha, which does not extend westward of the 
great plains and Rocky Mountains. P. hetero- 
stropha very rarely extends westward of the 
Mississippi River or southward of the Ohio and 
Potomac, and even at these boundaries it is 
largely replaced by other species. 
(67) 
