CHIEFLY OF THE UNITED STATES. 171 



Phtsa Nuttallii. pi. 24, fig. 93. 



Testa inflata, subtenui, subdiaphana, parum nitida. albida; spira obtusa, curta; suturis impressis ; anfract- 

 tibus quaternis, convexis, ultimo pergraudi et inflato; apertura grandi, subrotunda, subter marginem 

 pallido-fusca ; labro acuto, valde expanse ; columella leviter inorassata et contorta. 



Shell inflated, rather thin, semi-transparent, somewhat bright, whitish ; spire obtuse, 

 short ; sutures impressed ; whorls four, convex, the last one large and inflated ; aper- 

 ture large, rounded, pale brown within the margin ; outer lip sharp and very much 

 expanded ; columella slightly thickened and twisted. 

 Proc. Acad. Nat. Sci. 1864, p. 116. 



Hah. — Lewis' River, Oregon, Prof. Thomas Nuttall. 



My cabinet. 

 Diam. -27, Length -40 inch. 



Remarks. — Among the numerous new land and fresh water shells kindly given to 

 me many years since by the late Prof. Nuttall, were two specimens' of Physa, which I 

 did not describe then with the others, hoping that other specimens might be brought 

 by future travellers. Neither are not entirely perfect at the tip, and there is a slight 

 difference between them. It differs from all our American species in having a regu- 

 larly arched outer lip. It approaches Say's ancillaria, but it has not the shoulder, 

 and is rather more oblique. It seems to be a quite different species from concolor, 

 Hald., also brought by Prof. Nuttall from Oregon. The aperture is about five-eighths 

 the length of the shell. I have great pleasure in dedicating this species to my 

 deceased friend, who spent a long life in most successfully investigating and develop- 

 ing the beauties of nature. 



^a 



Phtsa anatina. PI. 24, fig. 94. 



Testa subfusiformi, subinflata, diaphana, tenui, albida; spira exserta, acuminata; suturis valde impressis; 

 anfractibus senis, convesiusculis, ultimo grandi ; apertura parviuscula, subconstricta ; labro subex- 

 panso, subter marginem incrassato et crocato ; columella medio impressa et contorta. 



Shell subfusiform, somewhat inflated, transparent, thin, whitish ; spire exserted, 

 pointed ; sutures very much impressed ; whorls six, somewhat convex, the last one 

 large ; aperture rather small and somewhat constricted ; outer lip a little expanded, 

 thickened and saffron color under the margin ; columella impressed in the middle and 

 twisted. 



Proc. Acad. Nat. Sci., 1864, p. 115. 



Ba6.— Northern Tributary of the Arkansas River, Kansas, F. Hawn, Civil En- 

 gineer. 



My cabinet. 

 Diam. -24, Length -49 inch. 



