126 THE NAUTILUS. 



Length, 5.0; diameter, 3.7; length of aperture, 2.5; width.. 

 2.0 mm. Topotype. 



Length, 4.5; diameter, 3.9; length of aperture, 2.4; width. 

 2.0 mm. Para type. 



Length. 4.0; diameter, 3.0; length of aperture, 2.0; width, 

 1.5 mm. Para type. 



Specimens of A. winkleiji measure: 



Length, 4.8; diameter, 3.1; length of aperture, 2.2. Nau- 

 tilus, Type. 



Length, 4.8; diameter, 3.0; length of aperture, 1.8; width, 

 1.5 mm. Topotype. 



Winkleyi is a species of the New England States, its original 

 locality being Saco, Maine, and that a form of this Amnicola 

 should be found in Ohio, and in a Pleistocene deposit, is sur- 

 prising. It is not unlikely, however, that winkleyi may occur- 

 in recent collections in the central States. The Ohio specimens 

 seem to depart varietally from the typical form as described by 

 Pilsbry (NAUTILUS, XXVI, p. 1, pi. 1, figs. 9-10). Some 

 thousands of specimens from this Pleistocene deposit show little 

 departure from the race as described above. Occasional globose 

 forms occurring with winkleyi show the relationship of the form, 

 although none have as wide a body whorl as the fossil race. It 

 is possible that this race may occur in other Pleistocene marl' 

 deposits. 



PHYSA ANATINA Lea. 



A large Physa occurring in the Rush Lake deposits differ* 

 slightly from anatina in being larger with shallower sutures and 

 more flat-sided spire whorls; the body whorl is wider as is also 

 the aperture; the spire is very sharply pointed and the colu- 

 mella has a distinct plait. Characteristic specimens measure 

 as follows: 



Length, 16.5; width, 9.0; aperture length, 11.5; width, 5.0 

 mm. Fossil. 



Length, 17.5; width, 10.0; aperture length, 13.0; width. 5.5 

 mm. Fossil. 



Length, 12.0; width, 7.0; aperture length, 8.5; width, 3.7 

 mm. Fossil. 



