90 NEW- YORK FAUNA — MOLLUSCA. 



Melania NIAGARENSIS. 



Melania niagarentU. Lka, Tr. Am. Phil. Soc. Vol. 8, p. 173, pi. 5, fig. 21. 



Description. " Shell smooth, obtusely conical, thick, horn-colored ; spire short ; sutures 

 linear; whorls rather flat ; aperture rather large, elliptical, within purple." This shell, Mr. 

 Lea states, has hitherto been confounded with M. depygis ; but according to that author, is 

 smaller, with a shorter spire and a narrower aperture. It has a purple columella and interior, 

 which in some cases are very dark ; the number of whorls is either six or seven, but all the 

 specimens were more or less eroded, and the apex removed : the aperture is nearly half the 

 length of the shell. 



Length, 0*55. Diameter, 0*25. 



Melania virginica. 



plate vii. fig. 141. 

 (state collection.) 



Pallidum virginica. Say, Nich. Ency. Ed. Am. Vol. 3, pi. 2, fig. 4. 

 Melania id. Id. American Concuology, pi. 47, fig. 2. 



Description. Shell tapering, elongate, often eroded at the tip. Whorls seven, but little 

 rounded, almost flattened, crossed by curved wrinkles on the spire and reclivate ones on the 

 body ; aperture subovate ; lip a little prominent towards the base. 



Color. Dull olive or black. A dull reddish line revolves near the base of the whorls, and 

 another near or upon the middle : occasionally destitute of the revolving bands. 



Length, O-5-l'O; of aperture, 02-0-3. 



This species varies so much with its locality and different stages of growth, that it is 

 exceedingly difficult to seize upon any distinctive character applicable to its various phases. 

 I have seen some specimens from the River Raritan, of a deep jet black varied with rufous. 

 I am not sure but that the following, with some, may be considered as a mere variety of this 

 species. 



