450 GASTEROPODA OF THE INFERIOR OOLITE. 



cincta, a Corallian species, and may possibly be identical. T. Lindonensis is rather 

 abundant in the " base-bed " at Lincoln {3£urchisonge-zone) , where it seems to 

 replace T. calix. Specimens of Trochotoma from the Ironstone of Duston also 

 possess considerable resemblance to the Lincoln shells. 



391. Teoohotoma funata, Lycett, 1850. Plate XLI, figs. 5 «, 5 &. 



1850. Trochotoma funata, Lycett. Ann. Mag. Nat. Hist., 2Dd ser., vol. vi, p. 417. 



1853. — — — Proc. Cotteswold Nat. Club, vol. i, p. 78. 



1854. — — — Morris, Cat., p. 280. 



Bibliographj, Sfc. — The acceptance by Morris of this species as an Inferior 

 Oolite fossil is a strong point in its favour, but owing to the absence of any 

 material evidence it was not listed by Hudleston and Wilson. Since that time a 

 specimen answering fairly well to Lycett's diagnosis has been obtained from the 

 Pea-o-rit of Nailsworth Hill. In some respects this specimen reminds me of 

 Pleurotomaria} 



Description : 



Height . . . . .12 mm. 



Basal diameter . . . .14 mm. 



Spiral angle ..... 65°. 



" Elevated, acuminated, nearly smooth ; whorls convex, their lower portions 

 flattened, with numerous encircling granulated ribs, faintly traced ; basal excava- 

 tion contracted. Height about equal to the basal diameter." 



The aperture of the figured specimen has greatly the aspect of Pleurotomaria^ 

 but I cannot find any trace of the sinus-band. 



Family— FISSURELLID^. 



Shell conical, limpet- shaped', apex, recurved', nucleus spiral, often disappearing 

 in the course of growth ; anterior margin notched or shell perforated ; muscular 

 impression horseshoe-shaped, open in front. 



There are three genera of this family in the Inferior Oolite, Bimula being the 

 most characteristically developed. In the case of Emarginula the anterior notch 

 is not always in evidence. It is probable that the shells in the Jurassic Rocks 



1 Lycett also described ^' Pleurotomaria funata^ 



