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Show 1879.] MOLLUSCA OF COSTA RICA. 485 38. S T E N O P U S M I C A N S , n. sp. (Plate X L . fig. 15.) Shell narrowly perforate, depressedly conical, thin, shining, nearly smooth, under the lens showing extremely faint oblique lines of growth, light fulvous brown ; whorls 5, very slightly convex, the last bluntly angled at the periphery ; sutures impressed; base flatly convex, with just traces of a very faint rudimentary keel between the umbilicus and the periphery ; aperture semilunar; outer lip simple, thin ; columellar margin very slightly expanded towards the umbilical region. Diam. 2, alt. 1| lin. Hab. Costa Rica. This species wants the marginal sutures and the thread-like carina of the preceding one. 39. STENOGYRA OCTONA?, Chemn. (Plate XL. fig. 16, animal.) This species conies remarkably close to S. octona, Chemn., which has a wide range, being found in Guayaquil, Brazil, and the West-Indian islands. I cannot detect any difference between this species and S. trochlea, Pfr., the habitat of which is given as Peru. Many specimens. Gabb gives as the habitat " Old Harbour." He describes the animal as " yellowish white, and wrinkled." 40. STENOGYRA OCTONOIDES, C. B. Ad., =8. contracta, Poey. Two specimens only. Costa Rica. 41. STENOGYRA GABBIANA, n. sp. (Plate XL. fig. 17.) Shell perforate, elongately turreted, moderately thin, pale straw-coloured, sculptured with somewhat distant raised thread-like descending striae, that are strongest on the upper whorls and become evanescent towards the sutures and the base of the last whorl ; whorls 8, convex; apex blunt, papillose ; aperture vertical, qua-drately semilunar; outer lip arcuate, thin, simple; columellar margin a little expanded over the perforation. Diam. 1%, alt. 3^ lin. Hab. Costa Rica. A single specimen. A somewhat sparsely and strongly ribbed species, distinct from <S. caraccasensis, Reeve, which is described by that author as a Bulimus. 42. LEPTINARIA INTERSTRIATA, Tate. Tornatellina interstriata, American Journ. Conch. 1870, p. 157. Shell minutely rimate, elongately ovate, turreted, thin, hyaline, ornamented with somewhat distant, raised, slightly curved longitudinal striae, that disappear towards the middle of the last whorl; whorls 6, convex; apex blunt, papillose; sutures margined; aperture ovately semilunar; outer lip simple, thin, arcuate; columella with a single sinuous fold truncated below. Diam. Ii, alt. 3 lin. A single specimen. Hab. Costa Rica. |