354 GASTEROPODA OF THE INFERIOR OOLITE. 



" Turbo." 



A certain number of smooth turbinate forms are classed provisionally under 

 Turbo. 



288. Turbo l^evigatos, Phillips, 1829. 



1829 and 1835. Turbo LjEVIGatus (Nerita l^vigata, Sow., Min. Conch.), Phillips. Geol. 



Yorks., pt. 1, pi. xi, fig. 31 ; and 3rd 

 edit. (1875), p. 330, pi. xi, fig. 31. 

 1885. Neritopsis (? Turbo) laevigata, Phil., pars. Hudleston, Geol. Mag., 



dec. 3, vol. ii, p. 49, pi. ii, fig. 3. 

 Cf. also ? Turbo gibbosus, d'Orligny. Terr. Jur., vol. ii, p. 342, pi. cccxxx, figs. 1 — 3. 



? Monodonta l.evigata, Thorent. Morris, Cat., p. 258. 



I must refer to my remarks in the ' Geol. Mag.' restricted to var. B. See 

 also antea, p. 344, with reference to " Neritopsis l&viqata" It still remains a 

 matter of doubt what the Phillipsian species may be. The specimen from the 

 York Museum, figured in the ' Geol. Mag.' (vol. cit., pi. ii, fig. 3) is, perhaps, the 

 nearest, but the system of undulating spirals seen in that specimen on close in- 

 spection is rather puzzling. I have in my own collection a similar but smaller 

 fossil from the Dogger, where such spirals are not noticeable. 

 ? Variety from the Lincolnshire Limestone, PL XXIX, fig. 1. 



Height ..... 6'5 mm. 



Width ..... 7-5 mm. 



Spiral angle (regular) . . . 95°. 



Shell smooth, turbinate, oblique, not umbilicated; spire subdepressed, apex 

 sharp. Number of whorls about five, smooth, tumid, and well marked off by the 

 suture. Body-whorl fully two-thirds the entire height, regularly convex, large and 

 without ornament other than broad growth-lines. Aperture wide and circular, 

 with a rather thin outer lip, and an excavated and slightly encrusted columella, 

 which carries no denticle, but is scored by a double furrow. 



Although there is a superficial resemblance to the turbinate forms described 

 above under Ataphrus, there are several indications which point to a different 

 genus. Thus the apex is sharp, not obtuse, the spire regular, the sutures are 

 impressed, and the texture, as shown by the broad growth-lines, is coarse. 

 In a second and smaller specimen which I possess these lines exhibit colour- 

 markings. The aperture is wide, and there is no actual denticle. 



