152 TF. H. Hndleston—On the Yorkshire Oolites. 



robust wide-angled variety is most conspicuous, though the narrower 

 forms are not deficient. 



Description. — var. elegans. Specimen from the Cornbrash (zone 

 4), Scarborough, Leckenby Collection. Plate VI. Figs. 8, 8a. 



Length 26 millimetres. 



Width of last whorl to length of shell 42 : 100. 



Approximate spiral angle 32°. 



Shell turrited, somewhat elongate, the spire increasing with great 

 regularity. The comjjlete spire would consist of about 12 whorls, 

 of which 7 are in good preservation. The earlier whorls are short, 

 tumid, and scarcely angular ; they are ornamented with spiral lines 

 of great regularity, one of which presently begins to develope as 

 a keel rather below the middle of the whorls, which, in that part 

 of the spire immediately posterior to the body-whorl, become more 

 angular, the upper half projecting outwards to meet the keel, 

 whilst the lower half is slightly constricted. The spiral lines 

 continue about the same in number, but increase in size with the in- 

 creasing whorls. These keels are split by a very shallow spiral groove. 

 Sutures close. The spiral lines in the anterior portion of the whorls 

 aire fewer and wider apart than those in the upper portion. A 

 similar style of ornament pervades the body-whorl, where a very 

 sharp and prominent tipper carina occupying a median position is 

 developed, and a very subordinate anterior one. This upper keel is 

 prolonged in a very stout digitation, which is broken off. There 

 is no trace of any digitation in connection with the anterior keel, 

 which seems to die out towards the margin. The canal sheath, or tail, 

 is broken off just where an apparent curvatui-e is commencing : 

 all this portion of the shell is ornamented with spiral lines, which 

 are rather finer than those on the spire. 



Relations, etc. — If I am correct as to the absence of a second 

 lateral digitation, the general characters of the spire fairly support 

 a relationship to the more typical fossils of the K.R. and L.C.G. 

 The spiral ornaments are bolder, and the whole shell is more vigorous 

 and more elegant than such a form as Fig. 7, which represents a 

 Kelloway Rock variety. From the L.C.G. fossils they differ in the 

 keel being a trifle higher in the whorls of the spire. The specimen 

 figured is the only one known to me from the Cornbrash. 



Var. pinguis. — Specimen from the Kelloway Eock (zone 5), 

 Scarborough. Leckenby Collection. Plate VI. Figs 9, 9a. 



Length 17 millimetres. 



Width of last whorl to length of shell 58 : 100. 



Approximate spiral angle 42° . 



Eight whorls are visible : the two highest without ornament and 

 almost globular, the others with spiral lines of great regularity and 

 fineness, those in the upper part of each whorl being the most 

 delicate. Keels prominent, median ; whorls slightly constricted 

 anteriorly. Body- whorl very large. Upper keel median, prominent, 

 sharp ; lower keel very subordinate. Regular spiral lines on the 

 columella, decussating with finer lines. Processes broken off. 



