April, 1920] Marl Deposits in Ohio 179 



Polygyra profunda Say, common, mostly large, diam, 30-33 

 mm., though some are smaller; the spire is rather flat, the 

 shell and lip strong. One shell, apparently normal (not 

 deformed), has no vestige of a tooth on the basal part of 

 the lip. 



Polygyra multilineata Say, abundant ; variable as to size (larger 

 diam. 18-26 mm.) and elevation of the spire. Some, 

 especially the smaller ones, have the umbilicus only par- 

 tially covered; one has a distinct tooth on the peristome 

 like that of profu7tda, and a few others have a vestige of 

 the same; one is reversed (sinistral). 



Polygyra albolabris Say, scarce; "one has a small parietal tooth. 



Polygyra thyroides Say, common; one specimen has the last 

 whorl exceptionally rounded, and also the aperture, espe- 

 cially in its basal part. 



Polygyra pennsylvanica Green, one found. 



Polygyra palliata Say, rather scarce. 



Polygyra tridentata Say, rather scarce, near the typical form. 



Polygyra fraudulenta Pilsbry, common, rather large and strong- 

 shelled. 



Polygyra monodon Rackett, common to abundant; variable 

 with respect to size, elevation of the spire and width of the 

 umbilicus, but there are no fraterna (and none approaching 

 it) ; in some specimens the parietal lamella is slightly but 

 plainly extending to the umbilical end of the peristome ; in 

 one, apparently nowise deformed, it is entirely within the 

 aperture. Most of the shells show more or less reddish 

 color, but some appear to be albinoes. • 



Polygyra hirsuta Say, frequent; a few have the umbilicus not 

 entirely covered; some have a distinct projecting tooth on 

 either side of the notch in the peristome. 



Strobilops labyrinthicus Say, rather scarce. 



Strobilops affinis Pilsbry, common to abundant. 



Vallonia pulchella Muller, fairly common; not chalky. A few 

 are apparently near excentria. 



Pupoides marginata Say, common, none chalky. Some appar- 

 ently mature, have no lip in the peristome or a slight one; 

 one is an albino. 



Gastrocopta ( = Bifidaria) armifera Say, rather scarce, all of the 

 typical form. 



