| OCR Text |
Show 1881.] SOCOTRAN LAND-SHELLS. 807 Medium specimen:- Major diam. 0*26, alt. axis 0*67, alt. apert. 0*28 inch. „ „ 6*9, „ 17*0, „ 7'5 millim. Locality. Eastern end of the island, on limestone. 11. BULIMINUS (ACHATINELLOIDES) SEMICASTANEUS, n. sp. (Plate LXVIII. fig. 9.) Shell rimate, solid, fusiform ; sculpture fine oblique striation, to the naked eye polished ; colour milky white on last two whorls, chestnut or sienna-brown on the five apical; spire elongately pyramidal, becoming rapidly attenuate at the apex, sides convex ; suture rather shallow ; whorls 7, body-whorl tumid, side convex ; aperture ovate, suboblique; peristome continuous as a strong callus on the body-whorl, rather flattened on the outer margin ; columellar margin with well-marked fold, oblique, somewhat thickened and angulate near the upper inner margin. Longest specimen :- Major diam. 0*22, alt. apert. 0*22, alt. axis 0*39 inch. „ ,5 5-5, „ 5*5, „ 10*0 millim. Shortest specimen:- Major diam. 0*22, alt. apert. 0*22, alt. axis 0*37 inch. ,, „ 5*5, „ 5*5, „ 9*5 millim. Locality. [South side of island on limestone rocks, nearly 1000 feet; nine specimens were found.-B. B.~\ 12. BULIMINUS (ACHATINELLOIDES) SEMICASTANEUS, var. ALBA (Plate LXVIII. fig. 10.) Shell fusiform, narrowly rimate, smooth; sculpture fine oblique somewhat irregular striation; colour all white; spire elongate, sides flatly convex, apex subacuminate, suture very shallow; whorls 6-7, sides very flat; aperture ovoid, subvertical; peristome sharp, continued as a thin callus on the body-whorl; columellar margin straight, with an internal plication, slightly reflected over the rimation. Size :- Major diam. 0*14, alt. axis 0*36, alt. apert. 0*18 inch. 3*7, „ 9*3, „ 4*7 millim. Locality- [S.W. of Gollonsir on the limestone ridge, over 1000 only 3 specimens were obtained.-B. B.~] This shell is very close to B. semicastaneus ; but it is much flatter on the sides and not so tumid in form, and is no doubt a local variety. There are only three specimens in the collection. 13. BULIMINUS (PACHNODUS) HELICIFORMIS, n. sp. (Plate LXIX. figs. 7, 7a.) Ovately fusiform, tumid, thin, diaphanous ; sculpture thin, a few transverse lines of growth; colour olive-brown; spire pyramidal, suture |
