OPEAS MAURITIANUM. 133 



2. 0. MAURITIANUM (Pfeiffer) . PI. 17, figs. 92 to 96. 



4 * Shell subperf orate, somewhat cylindrically turrited, 

 rather thin, striated (some of the lines more elevated), diaph- 

 anous, waxen; spire elongated, somewhat acute; whorls 7, 

 a little convex, the last almost equal to one-third of the 

 length of the shell, slightly tapering towards the base ; colu- 

 mella rather straightened. Aperture vertical, oblong-ovate, 

 peristome simple, unexpanded, the right margin evenly arcu- 

 ate, columellar margin very narrowly reflexed to the base. 

 Length 9, diam. 3, length of aperture 3, breadth iy 2 mm." 

 (Pfr.) 



Island of Mauritius (Pfr.) ; Petit Sable, Mauritius 

 (Mobius) . 



Bulimus mauritianus PFR., Proc. Zool. Soc. London, xx. 

 p. 150, (1852) ; Conch. Cab. (Bulimus) p. 86, pi. 30, f. 15, 16; 

 Monogr. iii, 1853, p. 402; iv, p. 462; vi, 100. f Subulina 

 mauritiana Pfr., NEVILL Proc. Zool. Soc. London, 1869, p. 

 64 (Mahe and Silhouette, Seychelles). Stenogyra (Opeas) 

 mauritiana Pfr., MARTENS in Mobius, Beitr. zur Meeresfauna 

 der. Insel Mauritius und der Seychellen, Reise nach Mauri- 

 tius 1874-75, p. 199. ? Stenogyra (Opeas) clavulinus P. & 

 M., G. NEVILL, Journ. Asiat. Soc. Beng. vol. 39, pt. 2, 1870, 

 p. 409 (Bourbon). 



Pfeiffer's description and figure (pi. 17, fig. 96) were from 

 an immature shell. When full grown (pi. 17, figs. 92-94, 

 Mauritius) there are fully 8 whorls. It is very glossy, only 

 weakly striate, and the spire has distinctly convex outlines, 

 being ivide above, with the subcylindric contour Pfeiffer men- 

 tions. This characteristic shape is much less noticeable in 

 young or immature shells, the form of which is fairly well 

 shown in Pfeiffer 's figure. The outer lip is moderately 

 arched forward. Length of an adult shell 11.5, diam. 3.4, 

 aperture 3.3 mm. 



The specimen shown in figs. 92 to 94 is from Mauritius. 

 The apex is badly drawn in fig. 92. Nevilles record of the 

 species from the Seychelles needs confirmation, as I learn 

 from specimens of Opeas received from him that his iden- 



