NERIN^A. 199 



Section C (TEiPLicATiE). 

 129. Nerin.ea pakva, Witcliell, 1887. Plate XIII, fig. 3. 



1887. NEEiNiEA PAKVA, Witchell. Vol. cit., p. 31, pi. i, fig. 5. 



Description : 



Spiral angle . . . .12° 



Height of whorl to width . . . 1 : 1*85 



Approximate length . . .45 mm. 



Shell cylindro-conical, strongly turrited. Whorls about eighteen, very short and 

 increasing by steps. In the earlier whorls the anterior portion is mnch excavated, 

 a feature which accentuates the sudden volutional increase. The depth of the 

 excavation continues to diminish until each whorl becomes nearly flat, but the 

 step-hke character is retained. In the later whorls the width is not quite so great 

 in proportion to the height. The hollows are ornamented by fine spiral lines, of 

 which there are no traces in the maturer whorls. 



Body-whorl angular and short, with a squarish aperture and very short canal. 

 Section triplicate ; one blunt and wide fold a little below the middle of the outer 

 walls, one rather wide fold on the columella considerably below the middle, and 

 one on the posterior wall. 



Relations and Distribution. — Distinguished from the succeeding species by the 

 excessive shortness of the whorls, and by their strongly step-like character. It is 

 also more free from dimorphism and of smaller growth. Somewhat rare on the 

 Oolite Marl horizon of Swift's Hill and Longridge. 



130. Neeinjia oolitica, Witchell, 1887. Plate XIII, figs. 4 a, 4h,4<c,4<d, 6, and 7. 



1887. NEEiNiEA OOLITICA, Witclicll. Vol. cit., p. 30, pi. i, fig. 1. 



Description : 



Spiral angle .... 12°— 16°. 



Height of whorl to width . , . 1 : 1-45. 



Length .... 80—120 mm. 



Shell cylindro-conical, turrited. Whorls twenty to twenty-five, exhibiting much 

 dimorphism. The apical whorls, as far as about the middle of the spire, are 

 much thickened at the suture and strongly excavated anteriorly, so as to produce an 

 appearance of excessive turritiug ; they are also ornamented with fine spiral lines. 

 Presently the thickening at the suture ceases, the whorls become nearly flat and 



