206 GASTEROPODA OF THE INFERIOR OOLITE. 



these may be doubtful in some instances. It is evidently closely related to some 

 of the species next to be described. 



My own specimens of N. Eudesii are from Weldon, where it is by no means 

 abundant. 



1-39. NERiNiEA Weldonis, sp. nov. Plate XIV, figs. 3 a, 8 &, 4, and ? 5 (apical 



conditions). 



Description : 



Spiral angle (regular) . . . 12° — 16°. 



Height of whorl to width, average . . 1 : 1'4. 



Approximate length . . .45 mm. 



Shell cylindro-conical, turrited. "Whorls from fourteen to eighteen, mode- 

 rately concave, the extreme depression being slightly anterior. The sutural 

 belt is tolerably prominent, but in the narrower varieties (3 a) the posterior 

 margin of each whorl constitutes the most marked prominence. Fine spiral 

 lines may be traced on the apical whorls, two very slightly granulated ones 

 showing a little above the others. These ornaments probably change with the 

 age of the whorls, but the available specimens are for the most part much 

 defaced. Columella ? hollow, with closed umbilicus. 



The aperture is subquadrate. Section triplicate ; one deep fold in the centre 

 of the outer walls, the fold on the lower part of the columella very small, the 

 fold in the posterior wall (upper columellar fold) deeply impressed. 



Relations and Distribution. — Differs from N. JSudesii in the smaller spiral angle 

 and less excavated whorl, although it undoubtedly approaches closely to the 

 Lincolnshire Limestone variety of N. Eudesii, which may be regarded as forming 

 the connecting link between N. Weldonis and the true Bathonian form. It also 

 has affinities with some varieties of Nerinsea oolitica^ and probably with certain 

 Bathonian Neringeas described and figured by Cossmann from beds in the north 

 and east of France. 



Forms such as fig. 3 a and fig. 4 are abundant at Weldon, which is in the 

 upper part of the Lincolnshire Limestone. These beds show some affinity to 

 the Great Oolite, but less so than those of Great Ponton. Fig. 5 is believed to 

 represent the apical conditions. 



1 There can be little doubt that these named forms are modifications, due to time and place, of 

 other named forms, and that they pass into each other. 



