W. S. Sudkston — On the Yorkuhire Oolites. 203 



This is almost in the same state of preservation as Fig. 12, the 

 matrix and replacements being very similar. The lines of growth 

 are exquisitely preserved, but no punct£e are visible. 



Belations and Description. — This shell has the turbinated v^horls 

 and other indications attributed to N. punctura from the Lower 

 beds. There is one important difference — the spiral angle is 15° 

 less. The " species " seems to be passing into something else. It 

 should be noted that Gasteropoda of this horizon are usually small, 

 whilst the more genuine Naticas are absent throughout the Lower 

 Calcareous Grit of Yorkshire. This form comes very near to Natica 

 Calypso, D'Orb., common in the Oxfordian of the Ardennes, both in 

 size and contour, but the French shell is less slender. 



With this elongated form the species referred to Natica terminate, 

 and surely it is stretching the limits of the genus to the utmost when 

 Natica cincta (Fig. 4) and JV^. tenuis (Fig. 13) are both included 

 within its ample folds. 



Cloughtonia, gen. nov. 



Shell short, conical, and solid, with a widish base, shell substance 

 thick. Whorls about five, flat and angular. Body-whorl more or 

 less bicarinated with slight depression of the intervening space. 

 Surface smooth or ornamented with rugose lines of growth (depen- 

 dent partly perhaps on the state of preservation). Aperture ovate 

 to ovate-oblong, rounded anteriorly. Pillar nearly straight and with 

 little or no callus. 



This genus has been constituted in order to receive a peculiar and 

 limited group of shells of which Cloughtonia cincta, presently to be 

 described, may be taken as the type. It appears to be intermediate 

 between the Naticas and so-called Chemnitzias, some species being 

 more nearly allied to the latter, some to the former ; it occurs where 

 the conditions may be regarded as peculiar, and to a certain extent 

 " estuarine." After disappearing from the Jurassic rocks of this 

 country above the Inferior Oolite, the genus reappears in the Port- 

 landian of Bucks and the Vale of W ardour, where two species were 

 described by me provisionally under " Pseudomelania" (see Gastero- 

 poda of the Portland Kocks, Geol. Mag. Sept. 1881, p. 889). 



Named from Cloughton Wyke, a bay between Scarborough and 

 Peak, where the type sj)ecies was first discovered, and where it is 

 not uncommon in zones 2 and 3. 



10. — Cloughtonia cincta, Phillips, 1829. Plate V. Fig. 14. 



1829, and 1835. Phasianella cincta, Phil., G. Y. pi. ix. fig. 29, p. 123. 

 1847. Phasianella cincta, Phil., D'Orb. Prod, de Pal. Strat. p. 267. 



1830. Natica {Etispira)? cincta Phil., Morris and Lycett, Gt. Ool. Moll. p. 113, 



pi. XV. fig. 20. 

 1875. Phasianella cincta, Phil., G. Y. 3rd ed. p. 259. 



Bibliography, etc. — Quoted in Phillips's 1st and 2nd editions from 

 " the Gray Limestone of Cloughton and Brandsby " ; in the third 

 edition from the " G. 0." ^ of the same localities. The specimen 



1 As this " G. 0.," so often used in the third edition, is very apt to impose upon 

 the unwary, it is as well to state that it does not mean Great Oolite, but Gre^ Oolite ! 

 From bad to worse one might say, as the Grey Limestone (zone 3) is very rarely 

 oolitic. 



