134 OPEAS MAURITIANUM. 



tifications of these difficult forms were sometimes ill-founded. 

 His 0. clavulinus from Bourbon was probably 0. mauri- 

 tianum, at least in part. 



Fig. 95 of pi. 17 represents a specimen from Maui, 

 Hawaiian Is., measuring length 12.7, diam. 3.5 mm. Like 

 the rest of the Opeas fauna of the Hawaiian group, it is 

 doubtless an immigrant there. I have also specimens col- 

 lected in "Washington, D. C., probably from a greenhouse. 

 They were sent about twenty years ago by Rev. E. Lehnert, 

 a reliable and at that time well-known collector. 



Opeas prestoni Sykes of Ceylon differs by having the spire 

 a trifle less obese, more straightly tapering than the most 

 strongly characterized 0. mauritiamim, yet in a series of 

 both, these differences would not serve to separate them if 

 mixed. I doubt whether the nominal rank of a variety can 

 be upheld except on purely geographic grounds. 



Yar. prestoni Sykes. PI. 17, figs. 98, 99, 100. 



Shell subperforate, long->cylindric, translucent, thin, cor- 

 neous or waxy-corneous, the apex somewhat obtuse; whorls 

 8%, plano-convex, longitudinally striated with growth lines, 

 the last whorl about nine-twentieths the total length; suture 

 well impressed; aperture elongate-ovate; peristome simple, 

 acute, the columellar margin narrowly reflexed to the base, 

 nearly covering the perforation. Length 11, diam. 3.25, aper- 

 ture 3x1.8 mm. (Sykes). 



Ceylon : Uda Pussellawa (Preston) . 



Opeas prestoni SYKES, Proc. Malac. Soc. Lond. iii, p. 73, 

 pi. 5, f. 4 (July, 1898). 



Fig. 98 is a copy of Sykes 7 original. Figs. 99, 100 are 

 from Ceylon specimens received from Mr. Collett. 



Var. olesispira Pilsbry. PL 17, figs. 101, 102. 



Shell minutely perforate, turreted, translucent, corneous, 

 the columella visible through the shell; glossy, with faint, 

 arcuate wrinkles. Lateral outlines of the spire decidedly 

 convex above. Whorls about 8%, moderately convex, separ- 

 ated by impressed sutures, which appear to have a trans- 



