152 WEST AMERICAN SHELLS 
It grows to the length of an inch, and lives in Ore- 
gon and Washington. 
Physélla columbélla, Hempl., the Columbia 
(River) Physa, has a pretty little shell, half an inch 
long, consisting of a short spire, and a very round 
and full body-whorl, with an ample aperture. It 
is of a brown color, but the curved columella is 
often white. From the river the name of which it 
bears. 
Apléxia hypnorum, Linn., the Moss 
Physa, (Bulinus hypnorum), is shown in 
Figure 132. Apex rounded, suture distinct 
and oblique, whorls six or seven, aperture 
moderate. Color, light brown, surface very 
smooth and glossy. This is a large north- 
x# ern species and it is also found in Utah. 
The variety tryoni, Currier, 1s collected in Mon- 
tana. 
Pompholyx effusa, Lea, the Puff Bubble, is a lit- 
tle creature that lives in the Sacramento river, also 
in the waters of Oregon, northern California and 
Nevada. The spire is exceedingly short, the aper- 
ture nearly circular and very large, the shell horny 
and sometimes ribbed; diameter a quarter of an 
inch. There are several varieties which have been 
deseribed, that differ shghtly in appearance. 
A very distinct and characteristic fresh 
9 water shell is shown in Figure 133, which 
; bears the name of Carinifex newbérryt, 
ae 2 Lea, Newberry’s Keel-shell. The whorls 
are few and are flattened at the top, while both 
above and below they are terminated by sharp, 
Xx $ 
