244 College of Forestry. 



NEW SPECIES OF AMNICOLID^ FROM ONEIDA 

 LAKE, NEW YORK 



By Henry A. Pilsbry 

 Academy of Natural Sciences of Philadelphia, Philadelphia, Pa. 



The New York State College of Forestry, under the direc- 

 tion of Professor Hugh P. Baker, is carrying on a biological 

 survey of Oneida Lake and has issued an interesting bulletin 

 upon the relations of mollusks to fish, by Frank C. Baker. 

 Some Amnicolidse obtained during this work, and subsequent 

 to the preparation of the bulletin, were submitted to the 

 writer. The collection proves to be of considerable interest, 

 including some species not before noticed. 



Amnicola bakeriana Pilsbry. 



The shell is umbilicate, turrited-conic, thin whitish-corneous, 

 somewhat translucent, with unevenly developed striation, dis- 

 tinct and close in places, weaker and sparse elsewhere. The 

 summit is decidedly obtuse, as in A. limosa, the first whorl 

 being nearly planorboid; subsequent whorls are evenly, 

 strongly convex. The aperture is very shortly ovate, almost 

 round, its length contained about 2^ times in that of the shell. 

 Peristome thin, in' contact with the preceding whorl for a 

 short distance. 



Length 4.3, diam. 2.7 mm. ; 5 whorls (type) 



Length 3.75, diam. 2.3, length of aperture 1.35 mm. ; 4 2/3 whorls 

 Length 4.1, diam. 2.75, length of aperture 1.65 mm.; 4 2/3 whorls 

 [Cotypes, New York State College o£ Forestry, No. 1048c] 

 Oneida Lake ; off Short Point in 8j/^ ft., mud bottom. Lower South 

 Bay, in 18 ft., on mud bottom. 



This species resembles A. limosa in the conspicuously obtuse 

 apex, but differs by the more elevated, turrited spire and the 

 smaller calibre of the whorls, hence smaller aperture. It is 

 also a weaker shell, with more whorls in specimens of the 

 same length. 



