76 SUBULINA, WEST AFRICA. 



simple and acute. The animal is dirty-white. Length 20 to 

 22, diam. 4 to 5 mm. (Rang) . 



Prince Island, at the foot of the mountains near the sea, in 

 numbers under stones (Rang). St. Thome at Boca Boa En^ 

 trade and Rio do Ouro; also Ilheo das Eolas (Greef) ; numer- 

 ous localities up to 750 meters (Newton). Also occurs on 

 the mainland. 



Helix striatella RANG, Ann. des Sci. Nat. xxiv, 1831, p. 

 38, pi. 3, f. 7. Achatina striatella MOREL., Ser. Conch, i, p. 

 26; Voy. Welwitsch, p. 79. GREEF, Zool. Anzeiger 1882, p. 

 519. PFR., Mono'gr. vi, p. 235. Stenogyra (Subulina) s., 

 DOHRN, Malak. Bl. 1866, p. 127. CROSSE, Journ. de Conch. 

 1888, pp. 25, 302. Subulina striatella GIRARD, Jornal de 

 Seiencias Math., Phys. e Nat., Acad. Real das Sci. de Lisboa, 

 (2) iii, p. 103 (August, 1893). WOLLASTON, Testae. Atlantica 

 p. 206 (Madeira, introduced). 



Achatina petrensis MORELET, Journ. de Conch, xiv, 1866, 

 p. 161 ; cf . Voy. Welwitsch p. 79. PFR V Monogr. vi, p. 235. 



Dohrn, who distinguished 8. angustior from striatella, gives 

 the following diagnosis of the latter: Shell turrit ed, thin, 

 whitish- waxen, glossy, longitudinally closely rib-striate, the 

 etriaB oblique to the axis; apex rather obtuse. Whorls 8 to 9, 

 a little convex, the last scarcely one-fourth the total length, 

 angular in the middle; columella arcuate, obliquely truncate. 

 Aperture oval. Length 20, diam. 5.5, aperture 4.5 x 3 mm. 



Plate 11, fig. 92 is a copy of Rang's original illustration. 



A large series from Cape Palmas, Liberia, Senegal, and 

 Prince Island is before me, none quite so large as the descrip- 

 tions of Dohrn and Rang indicate. A Liberian shell figured 

 (pi. 11, figs. 89, 90, 91) measures 18.5 mm. long, 4 wide, aper- 

 ture 4 mm. long, this being about the maximum size in a 

 series of some hundreds. The color is brownish-yellow. 

 Sculpture of very regular rib-striae, much weaker and in part 

 disappearing below the angle of the last whorl. In fig. 90 

 they are too strong on the base. The first 2 whorls are nearly 

 smooth and glossy, but show a regular crenulation below the 

 suture, apparently representing the elsewhere vanished rib- 

 lets, as in some species of Homorus. Whorls nearly 11. The 



