THE NAUTILUS. 17 



lected in that river. Most of his shells from Ohio were collected by 

 Mr. T. G. Lea or other resident collectors in the State. 



It is probable that Say's type is lost. I could not find it when I 

 went over the Academy's collection and made notes on his species, 

 and since the publication of Professor Wheeler's note Mr. Vanatta 

 has kindly made a search for it, and fails to find it. 



I confess that I am in doubt as to what Mr. Say had before him 

 when he described his Alasmidonta marginata, though I am inclined 

 to think it was the eastern form. In case it should be shown that 

 Say's name applies to the western shell, the name Alasmidonta 

 varicosa Lamarck, could probably be used for the Atlantic drainage 

 species. 



NEW VARIETIES OF FRESH WATER SHELLS. 



BY FRANK C. BAR EI!. 



Limnaea reflexajolietensis, i». var. 



Liinn&a reflexa atfenuata, Baker (non Say), Trans. St. Louis 

 Acad. Sci., Vol. IX, p. 20, pi. 1, fig. 4, 1901. 



Shell with an attenuated spire, the whorls, seven in number, being 

 very convex and the sutures very deeply impressed ; aperture about 

 a third the length of the entire shell, ovate, thickened on the inside 

 by a heavy callus ; peristome thin ; columella covered by a heavy 

 callus and with a prominent plait ; color light horn, frequently 

 blackened by the carbon dioxide in the water, aperture of same color,, 

 the internal callus edged with dark brown or red. 



Length 24.00; width 8.00; aperture length 0.50; width 5.25 mill. 



Length 23.00; width 7.75; aperture length 9.00; width 5.00 mill. 



Length 22.00; width 7.00; aperture length 8.75; width 4.75 mill. 



Length 29.00 mill. (Bryant Walker collection). 



Distribution : Joliet, Illinois (J. H. Ferris?) ; Saginaw River, 

 Michigan (Bryant Walker). 



Remarks: In the publication mentioned above the writer was led 

 into the error of identifying the Joliet specimens as attenuate/ Say. 

 Mr. Bryant Walker, to whom specimens were sent, has called the 

 writer's attention to the true characters of attenuata and to the fact 

 that the Joliet specimens are a distinct and undescribed variety of 

 reflexa The peculiar loosely coiled whorls, attenuated spire and 

 labiate lip will easily distinguish this variety. 



