305 



1912 Physa fontinalis scuta (Drap.), Hannibal, Proc. Mala. 

 Soc. vol. 10, p. 164 (part). 



Physa conoidea C. and F. 



1843 Physa osculans Haldeman (part), Mono. Limniades, pt. 



6, pi. 2, fig. 11. 

 1886 Physa mexicana conoidea C. and F., Miss. Sci. Mex., 



Moll. vol. 2, p. 101, pi. 39, fig. 8-8a. 



Aplexa nitens Phil. 



1837 Aplexa suturalis Beck, Index Moll., p. 117 {nomen nudum). 

 1843 Physa osculans Haldeman (part), Mono. Limniades, pt. 



6, pi. 2, fig. 13. 

 1845 Physa nitens Phil., Conch. Cab. (2), vol. 1, pt. 17, p. 5, 



pi. 1, fig. 1-2. 

 1886 Aplecta nitens Phil., Miss. Sci. Mex., Moll. vol. 2, p. 88, 



pi. 39, fig. la-lb. 



F. C. Baker (1926, p. 197) in a revisional paper on some fresh 

 water shells proposed that the name Physella Haldeman (1843, 

 p. 38) should replace the name Physa in North America on the 

 grounds that the North American forms differed anatomically 

 from the European. Baker emended Haldeman's description, 

 selecting the same type Physa {Physella) globosa Haldeman. 

 An examination of the original specimens of Haldeman shows 

 them to be materially different from any other known American 

 Physa. As mentioned by Pilsbry (1925, p. 326) the nearest 

 species in size and general form is that of Physa (Petrophysa) 

 zionis Pils. Both of these species occupy very unusual habits. 

 P. globosa is found on submerged rocks in the rapids at the mouth 

 of the Nolachucky River in eastern Tennessee. P. zionis lives 

 on the vertical canyon walls with algae in the seepage water of 

 springs. This last species is from Zion Canyon, Zion National 

 Park, Utah. 



The specimens of P. globosa described by Haldeman are 

 adult and as stated above differ materially from any other 

 known form. For this reason Baker is in error in his use of the 

 name Physella, which must be retained only for the single species 



