206 W. H. Hiidleston — On the Yorkshire Oolites. 



shells should be grouped under CyJindrites, but have never been able 

 to satisfy myself of the plication of the columella, though the 

 anterior portion of the aperture has a general resemblance to Morris 

 and Lycett's genus. Specimens, even the best, are in such a condi- 

 tion that a perfectly accurate diagnosis is almost impossible. 



Description. — Specimen from the Millepore Eock (zone 2), 

 Cloughton. Bean Collection. British Museum. 



i Height 16 millimetres. 

 gffaB;v^""l'.''.'!:f.::::.•.•::.■.• tV. ""■ 

 Body-whorl to total height 90: 100. 



Shell cylindro-conical, with a very short spire. The whorls of the 

 spire, about 3 in number, are subtumid, with a slope in the direction 

 of the spiral angle, suture distinct. The body-whorl is very long, 

 and large relatively to the spire : the shoulder is broad and nearly 

 square close to the suture, then droops towards the long compressed 

 sides ; it is very slightly tapered ofi" anteriorly. Shell very smooth 

 in its present condition. 



The aperture is extremely long and very narrow in the upper half, 

 but expands anteriorly owing to the hollowing out of the columellar 

 region. The columellar lip is thickened and drawn out obliquely. 

 No actual plication can be seen, owing to the imperfection of this 

 portion of the specimen. 



Belations and Distribution. — There is too much uncertainty about 

 these ill-preserved specimens for any serious attempt at correlation. 

 This species has been found sparingly in the Millepore Eock, and 

 probably in the Scarborough Limestone, and I have seen one specimen 

 from the Dogger. The specimen figured is above an average size. 



91. — AcTiEONiNA ciNEREA, sp.n. PI. V. Figs, 8, 8a. 



Description. — Specimen from the Scarborough Limestone (zone 3), 

 Cloughton. Leckenby Collection. 



Height 264 millimetres. 



Proportion of width to total height 61 : 100. 



Spiral angle 90°. 



Body-whorl to total height 80 : 100. 



Shell cylindro-conical, with a regular spire about one-fifth the total 

 height. The angle of increase of the spire is exactly a right angle. 

 Whorls of the spire probably 5, short, subtumid, and devoid of 

 ornament ; suture distinct. Shoulder of the body-whorl extremely 

 broad and square. Body-whorl relatively large and cylindrical ; 

 sides compressed, and almost constricted just below the shoulder, but 

 presenting on the whole a nearly straight outline. 



Shell substance moderately thin, without ornament, but marked by 

 rugose and slightly curved lines of growth, which also leave their 

 impression on the internal cast, a portion of which is visible in the 

 specimen. The aperture is partly involved in matrix, but is evidently 

 long, and extremely narrow in the posterior two-thirds, the outer lip 

 being very straight ; anterior portion of the aperture somewhat 

 restricted, with a short columella, which exhibits no signs of plication 

 (unless these have been effaced in developing the specimen) : termi- 



