217 



CALLIOSTOMA CONSTRICTUM. (N. Sp.) 

 Plate 28, figs. 4 and 4o, 



Shell conical, trochiform, length and breadth about equal : whorls 

 four or four and a half, those of the spire obliquely compressed : suture 

 distinct, flattened at nearly a right angle to the sides of the whorls or 

 somewhat excavated : last whorl about two-thirds of the entire length, 

 (in a dorsal view) concavely and shallowly constricted or grooved above 

 the niidde, most prominent a little below the centre : axis imperforate. 

 Aperture rhombic-ovate, outer lip thin and simple ; columella truncated 

 and ending in a prominent tooth-like process anteriorly : inner lip 

 expanded at its base and marked by a shallowly arcuate excavation 

 in front of the tooth-like process on the columella. 



Surface marked by numerous and rather fine revolving ribs, which 

 when examined by a lens are seen to be crossed by minute and densely 

 crowded oblique stria 1 . 



Length or height, seventeen millimetres and a-half : maximum 

 breadth, seventeen mm. : height of body whorl, eleven mm. 



East end of Maud Island, opposite Leading Island : one fine adult 

 specimen with the whole of the characters of the mouth well shown. 



ClNULIA PUSILLA. (N. Sp.) 

 Plate 28, figs. 5 and 5a. 



Shell very small, subglobose or broadly subovate in outline, its length 

 and breadth being very nearly equal : spire obtuse, short, about one- 

 fourth of the entire length : volutions three, the first and second 

 obliquely convex, the last large, ventricose and inflated: outer lip 

 thickened and margined exteriorly by a rather broad flat band which is 

 narrowest posteriorly : aperture narrow, ovately subpyriform, rounded 

 in front and pointed behind : columellar lip covered with a callus : 

 columellar folds not clearly distinguishable. 



Surface markings consisting of numerous spiral rows of minute shal- 

 low punctations, with broader and smooth flat spiral bands between 

 them. On the last volution and near the mouth, there are fifteen or 

 sixteen rows of spiral punctures, which latter are about one half as 

 broad as the smooth flat bands between them. Under an achromatic 

 microscope with an inch and a half objective, these spiral punctations 

 are seen to be transversely oval or somewhat rectangular in outline. 



Dimensions of a supposed adult specimen : length, nearly five 

 millimetres : maximum breadth, four mm. : height of last whorl as 

 viewed dorsal ly, three millimetres and three-quarters. 



