THE NATURAL HISTORY SURVEY. 245 
It is quite common, but has thus far been found only in the 
western and northern regions. The animal is very sluggish in 
movement and does not move about like the Pupez. It varies 
greatly in the number of teeth on the parietal wall, some hav- 
ing one, some two, and some three teeth, the percentage of 
each of these ina hundred being 3, 7 and 90. Specimens from 
Riverside have two teeth, the one placed in the center of the 
parietal wall being always the larger. When in progression 
the shell rolls from side to side in a very peculiar manner. 
PA MILY-COCHLEICOPEDZE: 
Shell: Elongated, polished, white or horn-colored; spire 
turreted, aperture rounded, one-third to one-half the length of 
the shell; columella short, arcuate to subarcuate, truncated or 
scarcely so; peristome simple, straight, somewhat thickened 
within. 
Anmmal: (See below under Cochhcopa),; radula differing 
from Achatinidz by the wide central tooth, which is narrow in 
the latter family. 
Distribution: World wide. 
Genus COCHLICOPA (Fér.) Risso, 1826.. 
Shell: Elongated, imperforate, shining, smooth, pellucid; 
whorls rounded; aperture one-third the length of the shell; 
columella more or less truncated; margins of peristome joined 
by a callus. 
Animal: Foot truncated before, roundly pointed behind; 
mantle thin; respiratory and anal orifices on right of body, 
just beneath the peristome of the shell; generative orifice be- 
hind the right eye-peduncle; no caudal mucus pore or locomo- 
tive disk. 
Jaw: Long, low, wide, arcuate; ends blunt; cutting edge 
with a single large median projection; anterior surface not 
ribbed, but striate. Lingual membrane with central tooth long 
and narrow, tricuspid; laterals as wide as high, bi- or tricuspid; 
first marginals modified laterals; outer marginals wide, low, 
multicuspid. Genitalia with a short, stout penis sac “with the 
retractor muscle near its base; the vas deferens enters at its 
apex, and near its entrance into the vagina it receives a curious 
flagellate appendage, swollen below, narrow above, as long as 
the whole system, with a large, narrowly ovate bulb at its end; 
