144 MOLLUSCA. 
A variety from Lake George (Oregon) must be very corpulent. It 
is much decollated, and is light and thin. Whorls convex; aperture 
rounded-ovate; lip very flexuous, having a sinus posteriorly, and a 
very deep one at the point of the columella; colour pale olive-green. 
Even the little M. stliqua, may be only a starved specimen of the 
Nisqually variety. All have a varix half a volution from the mouth. 
Figure 165, specimen from Lake George, viewed by the aperture. 
Ceriruium (Poramts) sacratum (Gould). 
Testa rudis, elongata, badia et fascia luted cincta: spira turrita, anfrac- 
tibus ad decem convexis, viz angulatis, et liris obsoletis cinctis, supernis 
plicatis, ultimo globoso, abnormal, varice crasso munito ; suturd pro- 
funda, litea: apertura rotundata, antice effusa, haud emarginata ; 
labro everso, polito, piceo: operculum multispirale. 
Cerithium (Potamis) sacratum, GouLp ; Proceed. Boston Soc. Nat. 
Hist., 11. 118. Expedition Shells, 60. 
Suet rather thin, turreted, of a dark chestnut or umber colour, 
with a faint orange band around the middle of each whorl. Whorls 
ten or more, convex, somewhat angular, slightly plaited near the tip, 
everywhere roughened by the stages of growth, a few indistinct, raised 
lines surrounding them; sutural region deeply impressed, and of a 
pale yellow colour ; the last whorl is rather globular, disproportionately 
large, and having a very large varix, or rather false aperture to the 
left. Aperture moderately oblique, effuse at the base of the colu- 
mella, but not notched ; outer lip everted, advancing, simple, of a deep 
chestnut or pitch colour. Operculum circular, horny, multispiral. 
Length an inch and a half; breadth five-eighths of an inch. 
Inhabits Sacramento River, California. 
Allied to C. varicosum, Sowb. The surface, though not smooth, is 
destitute of longitudinal ribs, except near the tip: it has also a pale 
sutural region and a less marked canal. C. Hegenischii, Pfeiffer, is 

