46 



LAND AND FRESH-WATER SHELLS OP N. A. [PART IL 



Fig. 62. 



Limnaa 

 nuttalUann. 



sutures impressed ; whirls six, convex ; aperture ovate, inflated, banded 

 within. 



Oregon. My cabinet and cabinets of Prof. Nuttall and Dr. 

 Jay. Diam. .50, length .95 inch. 



A fine, rather robust species, rather resembling L. elodes, 

 Say, but shorter and more inflated, and having a larger and 

 more curved fold. The aperture is rather more than one- 

 half the length of the shell, and is refuse at the lower part. 

 Under the lens may be observed very minute revolving striae. 

 The band within the aperture is removed from the edge of the 

 lip, and is broad and brown. The lip is not reflected. {Lea.) 



A recent visit to Prof. Haldemau has enabled me to examine 

 the two original specimens, the only ones known, from which 

 were drawn the description of Limnaea expansa. Believing them 

 accidental variations only, I add them to the synonymy of Limnsea 

 elodes. The Oregon specimen, 8573 of the collection, most nearly 

 resembles this form. A fac-simile of Haldeman's figure and a 

 copy of his description here follow : — 



Limnsea expansa. — Shell short, smooth, translucent, and fragile ; body 



whirl inflated ; spire as long as the aperture, and rapidly attenuated to an 



acute apex ; whirls five, somewhat flattened ; suture shallow, 



but very distinct, aperture efiuse ; fold on the columella deep 



and distinct. Color brownish ochre-yellow. 



Found only in Vermont. 



I owe the opportunity to describe this new species to Dr. 

 Gould, who gave me specimens, and the information that they 

 are from Vermont. It diflers from L. elodes in having a 

 polished surface, expanded aperture, obsolete lines of growth, 

 translucency, and a deeper fold upon the columella. It can- 

 not be confounded with any other species. (Ilaldcman.) 



It must constantly be borne in mind that I cannot 



pretend at this time to speak very positively in regard to the 



„. „, synonymy of the North 



Fig. 64. . T • 



American Limnaiidae. My 



conclusions are the best I 



can arrive at with my 



present material. It is a 



point to be decided in 



future whether L. nuttalli- 



ana and L. expansa are 



L. elodes. L. eo-pansa. L. nuttalliana. gynonyms of L. palustris. 



The forms referred to this species are shown at one view in Fig. 64. 



Fig. 63. 



