PHYSA, 



75 



Fie. 121. 



Fig. r. 



Planorhis newberryi, Lea, Proc. Phila. Acad. Nat. Sc. 1858, 41, 



Fig. 120 is drawn from the original 

 specimen in Mr. Lea's cabinet. A 

 more elevated form is figured also. 



It has also been found in Clear 

 Lake, California. 



Another form of this species is 

 figured in Fig. 122, It is less cari- 

 nated, much more rounded in the whii'ls, but apparently identical 

 with C. newberryi. It is from Pitt River, California. 



O. newberryi. 



C. newberryi. 



Fig. 123. 



PHYSA, DRAPAENArD, 



Tentacles slender, setaceous. Mantle covering part of the 

 shell, the margin fringed or digitate. Foot 

 long, acuminate behind. 



Shell sinistral, oblong, thin and polish- 

 ed ; spire acute 5 aperture oval, rounded 

 anteriorly, not dilated ; inner lip spread 

 over the last whirl, simple in front ; outer lip 

 acute. 



Jaw single, superior, chevron-shaped, fffj10^^ 



Jaw of Pki/sa, 



Physa hderostraj^uu 



Fig. 124. 



A 



Lingual membrane 



This genus is widely distributed over the globe, and is nume- 

 rous in species in this country, where it extends more southerly 

 than Limnsecu In its habits it is more active than the other 

 Limnseidse, both in walking and in gliding, shell downwards, on 

 the surface of the water. 



It will be seen in the generic descriptions of Physa and Buli- 

 nus that the former name is restricted to those species having a 

 digitated mantle, and the latter applied only to those whose 



