EST RES oa eR PE 
el il Pe a, . / 2! : ™ 
150 THE CHICAGO ACADEMY OF SCIENCES. 
with three cusps, of which the central one is very long and the 
side cusps are (generally) subobsolete, the cutting points well 
developed; lateral teeth similar to the central tooth, but with 
side cusps distinct; marginal teeth with a small base somewhat 
quadrangular in shape, and with irregularly shaped cusps, the 
inner being several times longer and broader than the outer 
cusp; both have well developed cutting points. The transition 
Fie. 19. 
Radula of POLYGYRA PROFUNDA Say. (Original.) c, central tooth; 
1, first lateral; 18, intermediate lateral; 22, 27, 28, 32, marginal teeth. 
from lateral to marginal teeth is very gradual, and it is diffi- 
cult to determine just where one set ends and the other begins 
(Fig. 19). Several teeth in one membrane examined (37-I-37) 
had the inner cusp bifid (27-32 in figure). Mr. Binney says: 
“but the change from laterals to marginals is very gradual, 
being made without splitting of the inner cutting point, which 
is simple on the extreme marginals even.’”’* 
This membrane was undoubtedly a pathological specimen. 
There are over 120 rows of teeth. 
Genitalia: ‘The penis sac is not very stout, long, receiv- 
ing the retractor muscle at about the middle of its length, and 
tapering very gradually towards its summit into the vas defer- 
ens; genital bladder large, globose-oval, on a long, narrow 
duct.” (W. G. Binney.) 
Distribution: Western New York to Minnesota, south to 
Virginia and Mississippi. 
Geological distribution: Pleistocene; Loess. 
Haiitat: Found in large numbers in woodlands where 
there is moisture, under dead underbrush and old logs. 
*Manual Amer. Land Shells, p, 318. 
