18/8.] ON NEW LAND AND MARINE SHELLS. 311 



I have established this genus for the reception of certain species 

 of land shells that have hitherto been included in the genus Megalo- 

 mastoma of Guilding, a natural West-Indian group, from which, 

 however, they appear to me to differ so greatly in several important 

 characters that I do not hesitate to separate them from the Megalo- 

 mastomata as a distinct natural group, having its habitat in Madagas- 

 car and the Mascarene Islands. 



The type of my genus Mascaria is the Cyclostoma croeeum of 

 Sowerby, which has been placed iu the genus Megalomastoma by 

 H. & A. Adams, Pfeiffer, Troschel, and other authors. With it 

 must be included a species recently described by M. Morelet, in the 

 'Journal de Conchyliologie ' (tome xvii. No. 2, April 1877), under 

 the name of Megalomastoma litteratum. 



Mascaria crocea is peculiar to the Mauritius, where it was found 

 alive by Sir David Barclay on the hills in the neighbourhood of 

 Black River. M. litterata is from Madasgascar, and was collected 

 there in some abundance by Mr. Waters. 



5. Descriptions of nine new Species of Land and Marine 

 Shells from various localities. By George French 

 Angas, C.M.Z.S., F.L.S., &c. 



[Received February 16, 1878.] 

 (Plate XVIII.) 



Bulimus watersi, n. sp. (Plate XVIII. fig. 1.) 



Shell imperforate, elongately turreted, rather thin, shining, finely 

 irregularly longitudinally striated, the striae here and there forming 

 tessellated rows and patches, pale olive, lighter towards the apex, 

 mottled with small brown spots and irregular markings, with indica- 

 tions of two paler bands, one below the suture, and the other towards 

 the base of the last whorl ; spire acuminate, somewhat obtuse at the 

 apex ; whorls 9, rather convex, the last of equal length with the 

 spire ; sutures impressed and slightly crenulate ; aperture subovate, 

 one third the length of the shell, pale violet within ; outer lip simple, 

 scarcely thickened at the edge ; columella with a slight callus below, 

 a little arcuate towards the base. 



Alt. 3 inches, diam. 1 1 lines ; length of aperture 1 inch. 



Hab. Madagascar. 



This species is allied to B. obtusatus, Gmel., and B. moreleti, 

 Desh., with which, including perhaps B. clavator, Petit, and B. 

 balstoni, Angas, it combines to form a natural group of Madagas- 

 car Bulimi. The specimen from which my description is taken is 

 iu the collection of Sir David Barclay. There is a second example 

 in that of Mrs. De Burgh. 



I would here correct the name of a species in the list I gave in the 

 Society's ' Proceedings' for 1877 (p. 527), of certain land shells from 

 the Island of Madagascar that had been submitted to me by Mr. 



