144 OPEAS, WEST AFRICA. 



10. 0. ACMELLA (Morelet). PL 24, fig. 37. 



1 ' Shell rather small, turrited acieulate, apex a little ob- 

 tuse, crystalline, smooth. Whorls 7 slightly 'Convex, mar- 

 gined with a denticulate suture ; the last whorl equal to one- 

 fourth of the entire length of the shell. Aperture ovately 

 lunate, with simple, arcuate margins, columellar margin a 

 little dilated above, reflexed. Length 4.5, diam. 1.25 mm." 

 (Morelet) . 



West Africa: environs of Mayomba, 120 miles N. W. of 

 Loango. 



Stenogyra acmella MORELET, Journ. de Conch. Jan. 1885, 

 p. 26, pi. 2, f. 4. 



" After Stenogyra pusilla from the Comoros which meas- 

 ures only 3 mm. in height, this species is the smallest that is 

 known to me. The columella of this species is not truncated ; 

 the whorls of the spire, a little convex, are joined by a nar- 

 rowly margined suture, where the incremental strige, which 

 disappear on the rest of the surface, assume the form of 

 fine and regular folds. The shell is white, transparent and 

 crystalline. ' ' (Morelet) . 



11. 0. RECISUM (Morelet). PI. 24, fig. 38. 



Shell imperforate, shortly turrited, thin, with arcuate in- 

 cised striae, hyaline, corneous, very glossy, pale brown. Spire 

 conoidal, apex rather obtuse. Whorls 6 plano-convex, the last 

 enlarged, exceeding one-third of the entire length of the 

 shell. Aperture semioval, margins simple, the columellar 

 margin sinuous, shortly revolute above. Length 6; diam. 

 2.25mm." (Morelet). 



W. Africa : Mayomba, 120 miles N. W. of Loango. 



Stenogyra recisa MORELET, Journ. de Conch. Jan. 1885, p. 

 28, pi. 2, f. 5. 



"This little species, at first sight, recalls a little our 

 Ferussacia lubrica, of which it has the gloss and form. It is 

 composed of six whorls a little convex, and the last relatively 

 more developed, which gives it the appearance of a Bulimus. 

 The aperture, in consequence, is rather large in proportion to 



