ae Re eae Pa 3 
OO ee, Sn 
: : Pathe eam s 
146 THE CHICAGO ACADEMY OF SCIENCES. 
of the base of attachment, the side cusps short; lateral teeth 
similar to the central tooth, but bifid, the inner cusp long and 
wide; marginal teeth at first resembling laterals, but the inner 
cusp soon lengthens, becomes bifid, and assumes the usual 
form of marginal. 
Genitalia: ‘‘The penis sac is long, cylindrical, receiving 
the vas deferens and retractor muscle at its summit; genital 
bladder small, globular, with a long duct, which is narrow 
above but below its middle gradually enlarges to greater than 
the width of the bladder.” (W. G. Binney.) 
Distribution: Southern New York to Michigan, Canada to 
North Carolina, Alabama and Kentucky. (Pilsbry.) - 
Geological distribution: Pleistocene; Loess. 
Habitat: In open woodlands in the vicinity of water, under 
and about logs, and débris of various kinds. 
Remarks: Aspecies distinguished from znflecta by its open 
umbilicus and larger size. It is quite rare, and has thus far 
been found only in the southern region, and the specimens are 
rather small. The shell is carried ata slight angle during pro- 
gression, which is rather slow. 
53- Polygyra fraudulenta Pilsbry, pl. xxx, fig. 7. 
Flelix fallax W.G. BINNEY. (non Say.) Man. Amer. Land Shells, p. 292. 
Polygyra fraudulenta PiItsBry, Proc. Phil. Acad. Sci., p. 20, 1894. 
Shell: Differing from tridentata in having “a compact shell 
of a reddish-brown color (varying to white in some localities) ; 
the spire is low-convex, composed of six closely coiled whorls, 
the last being notably deflexed in front and strongly con- 
stricted behind the lip. The aperture is strongly “dished” or 
basin-shaped; the outer lip bears a broad tongue-shaped in- 
flected tooth, situated at the position of the periphery of the 
shell. The middle part of the basal lip bears a small squarish 
tubercle, which is often laterally compressed. The parietal 
wall bears an elevated oblique blade which is typically almost 
straight and never much curved.” (Pilsbry.) (Fig. 16, B.) 
Greater diam., 15.00; lesser, 13.50; height, 8.50; umbilicus, 3.50 mill. (8448.) 
= tS WA ODs SRS ES aes 8.50; & 3.50 “ (8455.) 
Animal: As in tridentata, but generally a little darker. 
Faw: As usual, with twelve ribs. Binney gives fourteen 
ribs. 
Radula formula:* 1$3+§+13+4413+4+12 (27—-1—27). 
*This radula is from a Southern Illinois specimen. See The Nautilus, Vol. XI., p, 30, 
1897. 
