NEW FRESH WATER AND LAND SHELLS. 189 



Remarks. — This is a beautiful species. The most perfect specimens are re- 

 markable for their fusiform shape and their long aperture, which presents a 

 curved columella and extended sinus somewhat like the genus lo. The bands 

 in some individuals are numerous and distinct, the largest being nearest the 

 base. The tubercles form a row round the middle of the whorls of most speci- 

 mens, but in some, though rarely, this part is carinate or rounded. Some are 

 slightly tuberculated below the suture. Among the young specimens some 

 are costate near the apex, others entirely smooth and without bands. I owe 

 the fine specimen figured to Mr. Dutton, after whom I name it. 



Section VII. — Granulate Melanin. 

 Melania Holstonia. Plate 6, Fig. 55. 



Testa granosd, conoided, subcrassd, nigra; spird subelevatd; suturis impressis; anfractibus superne 

 planulatis ; aperturd ovatd, purpurea. 



Shell grained, conical, somewhat thick, black; spire somewhat elevated; sutures impressed; whorls flat- 

 tened above ; aperture ovate, purple. 



Hab. Tenn. Dr. Troost. Holston River, Tenn. Mr. S. M. Edgar. 

 My Cabinet, and Cabinets of Dr. Troost and Mr. Edgar. 

 Diam. .33, Length .79 of an inch. 



Remarks. — A very distinct species with four series of small, rather sharp 

 elevations round the whorls, the two inferior ones rather indistinct. Only two 

 specimens have come under my notice, and both have the apex decollated. 



Section VIII. — Cancellate Melanin. 

 Melania caliginosa. Plate 6, Fig. 56. 



Testa cancellatd, conoided, subcrassd, transverse striatd, tenebroso-fuscd ; spird elevatd; suturis 

 enormiter impressis; anfractibus octonis, subconvexis ; aperturd parvd, ellipticd, intus purpuratd. 



Shell cancellate, conical, somewhat thick, transversely striated, very dark brown; spire elevated; sutures 

 irregularly impressed; whorls eight, rather convex; aperture small, elliptical, purplish within. 



Hab. Tenn. Dr. Troost. 



My Cabinet, and Cabinets of Dr. Troost and P. H. Nicklin. ' 

 Diam. .34, Length .91 of an inch. 



