220 LAND AND FRESH-WATER SHELLS OF N. A. [PART IV. 



on the columella; aperture small, elliptical, withiu whitish, subna- 

 creous ; columella uot indented ; sinus small. 

 Habitat. — Alabama. 



Fie 437 Fie 438. Diameter, -30 (8 millim.) ; length, -75 of an inch 

 (19 millim.). Length of aperture, -33 (8 millim) ; 

 breadth of aperture, -17 of an inch (4 millim.). 



Observations. — A singularlj' pale, greenish-white 

 species, the distinguishing marks of which are 

 its regular, subcyliudric form, and the smooth 

 spire, combined with the prominent stria? at the base of the shell. 

 These are characters which I do not recognize on any other species 

 so combined. There is also a distinct carina on the penultimate 

 whorl, near the top of the aperture, above which may be observed 

 a faint, interrupted line. — Anthony. 



Another specimen in Mr. Anthony's collection has not the 

 angulation so well developed and is covered with slight striae. 

 The type specimen is figured, figure 438. 



108. G. rhombiea, Anthony. 



Melania rhombiea, Anthont, Ann. N. Y. Lye. Nat. Hist., vi, p. IIG, t. 3, f. 16, 

 March, 1854. Binxet, Check List, No. 228. Brot, List, p. 38. Reeve, Monog. 

 Melania, sp. 347. 



Description. — Shell conic, rather thin, brown ; spire regularly pyram- 

 idal ; not elevated ; whorls about six, flat, regularly and very j.j_ ^g_ 

 distinctly striate; body- whorl angulated about the middle, 

 nearly smooth, except as modified by the lines of growth, 

 which are quite distinct, the concentric striae being nearly 

 obsolete on the body- whorl ; sutures inconspicuous ; apertui-e 

 rather large, ovate, whitish within ; columella very slightly rounded, 

 with little or no sinus. 



Habitat. — Alabama. 



Diameter, *22 (5^ millim.); length, •43 of an inch (11 millim.). 

 Length of aperture, -20 (5 millim.) ; breadth of aperture, -12 of an 

 inch (3 millim.). 



Observations. — This cannot well be confounded with any known 

 species; its short spire, flat, striated whorls, regularly and rapidly 

 decreasing to the apex, the pi'ominent, acute carina, which encircles 

 it near the top of the aperture, beneath which the stria>, so promi- 

 nent above are hardly discernible, and its rather broad form, will 



