GOKIOBASIS. 281 



lower ones subconvex, smooth, upper oues flattened and carinate 

 near their bases; sutures slight; aperture narrow, ovate, within pale 

 purple ; columella regularly curved ; sinus not remarkable. p,j„ ^^^ 



Habitat. — Tennessee. 



Observations. — May be compared with M. exilis, Hald., than 

 which it is more slender, more attenuate and of more solid 

 texture: its color is also entirely different, being more like 

 M. Warderiana, Lea, but wanting the peculiar, bulbous form 

 of that species. The carinations do not extend to the three lower 

 whorls ; upon these they are entirely wanting. It is a peculiarly 

 slender and graceful species. — Anthony. 



Goniobasis Grosvenorii. — Shell smooth, subattenuate, thin, horn- 

 color, bright without bands ; spire subattenuate, pointed, carinate at 

 the apex ; sutures regularly and very much impressed ; whorls eight. 

 Fig. 54C. convex; aperture small, subrotuud, white within; outer lip 

 acute, slightly sinuous; columella bent in, thin and contorted. 

 Habitat. — Fox River, Illinois; H. C. Grosvenor: and Quincy, 

 Ohio; J. Clark, 

 Diameter, -29; length, -79 of an inch. 



Observations. — I have about a dozen specimens from Quincy, 

 and one from Fox River. The former are fresh, and of a dark horn- 

 color. The latter is whitish and probably bleached, being evidently a 

 dead shell. It is allied to J/, varicosa, Ward, and is very much the 

 same outline and size, but it has no veins and has no light line below 

 the sutures. The aperture is not quite one-third the length of the 

 shell. I name it after Mr. Grosvenor, to whom I am indebted for the 

 specimen from Fox River, and many other species. — Lea. 



Messrs. Anthony and Haicleman's species, described above, 

 arc all figured from their types. Mr. Lea's are copies from his 

 plates. The shells indicated b}' the above several descriptions 

 embrace ver}^ great variety in form and convexit}^ of the whorls, 

 still I cannot, with several thousand specimens before me, as- 

 certain the dividing line, they all seem to merge together. 



With regard to exilis, Hald., there is no doubt of the type 

 belonging to this species, but a very narrow, elongated form, 

 of many flattened whorls, has received the name exilis in most 

 of our collections, although it does not at all reseml)le the 

 tj'pe, but is a new species, G. Haldemani (nobis). G. spmicar- 

 inata is found in Kentucky, Tennessee and in all the North- 



