STENOGYBA. 195 



erably smaller and more rapidly tapering than S. octona, which has its colu- 

 mella somewhat truncated, and has not as yet been found on this continent. 

 This, according to Mr. Bland, is not the true S. subula (q. v). 



Stenogyra subula, Pfr. 



Shell subperforate, subulately turreted, delicately striated, shining, transpar- 

 ent waxen ; whorls 8, rather convex, the last about equalling two sevenths of the 



length ; columella straight ; aperture oval-oblong ; peristome sim- 



o > 6 > r o ' f Fig 99 



pie, acute, its right extremity straight, its columellar extremity very 

 slightly reflected, appressed. Length, lH mill. ; width, 3 mill.: 

 of aperture, length, 3 mill. ; width, 3^ null. (Pfeiffer.) 



Stenogyra subula, Pfeiffer, Mon., II. 158, not of Binney, etc. 



A West Indian species introduced into the Southern Region at 

 Mobile. 



For jaw and dentition see ante, p. 191, Fig. 97. (PL IV. Fig. 

 P., b is an extreme marginal.) There are 24 — 1 — 24 teeth, with 

 6 perfect laterals. 



There were eggs in the oviduct of the Mobile individuals examined by me. 



It must be borne in mind that this is not the shell described and figured un- 

 der this name in Vol. II., and Land and Fresh- Water Shells, I., which is S. octo- 

 noides, D'Orb. (See above.) 



Subgenus MELANIELLA, Pfr. 



Animal not observed. 



Shell imperforate, ribbed, usually decussated, sculptured, brownish horn-col- 

 ored, rather solid; whorls 9, rather convex, graduated, the three or four upper 

 ones without ribs ; aperture effuse at base, ovate ; columella constricted ; peri- 

 stome simple, subcontinuous. 



A West Indian subgenus. One species has been introduced into the Flor- 

 ida Subregion. 



Stenogyra gracillima, Pfr. 

 Vol. III. PL LIII. Fig. 3. 



Shell imperforate, minute, elongated, very slender, thin, of a drab-white 

 color, ornamented with elevated, compressed, sharp, rather distant, longitudinal 

 ribs, of which there are from 20 to 30 on each Avhorl, the interstices sculptured 

 by very crowded lines ; spire obtuse at the apex, and composed of about 8 

 flattish whorls, the last of which is about one fourth the length of the shell, and 

 somewhat angular below the middle; suture deeply impressed; aperture small, 

 elongated, rhomboidal-ovate ; peristome sharp, and somewhat pressed inward, 

 so as to be parallel to the axis ; the columella is straight, and joins the peri- 

 stome at an angle, so as almost to form a notch at the base of the aperture. 

 Length, 7 mill.; diameter, If mill.; aperture, 2 mill, long, 1 wide. 



