﻿556 J. 8. Gardner— ^JVotes on Cretaceous Gasteropoda. 



V. — Notes on Cretaceous Gastekopoda. 



By J. S. Gardner, F.G.S. 



(PLATE XVI.) 



IN May last I had the honour of laying before the Geological 

 Society a description of all the known British Cretaceous PatelUdoe, 

 and patelloid Gasteropoda. Since then the well-known collector, 

 Griffiths, of Folkestone, has forwarded to me a new limpet from 

 Hythe, which appears to belong to the genus Hipponyx. The finding 

 of a shell of this genus is remarkable, as hitherto the shelly bases were 

 the only indications of the existence of Hipponyx in Cretaceous rocks 

 in England, whilst Capulus Dunlcerianus, d'Orb., was the only shell 

 on the Continent, of this age, which could be referred to the genus. 



Hipponyx neocomiensis, sp. n. PI. XYI. Fig. 1. 

 Lower Greensand, Hythe. 

 Conical, cap-shaped, very elevated, front flattened and com- 

 pressed, posterior flattened and slightly hollowed, margin slightly 

 quadrate. The cast shows the shell to have been very thick, and 

 there are indications of coarse ribbings ; the beak was probably solid 

 and overhung the posterior margin. ' The dimensions are large, as 

 seen by a reference to the figure. The great size of this and all 

 Gasteropods from Hythe compared with those from other British 

 Lower Greensand localities is truly remarkable. 



Dentalium major, sp. nov. PI. XVL Fig. 2. 

 Cast bed, Grey Chalk, Dover. 



Tubular, symmetrical, slightly curved, very gradually tapering; 

 surface evenly striated near the apex, plain and rather rugose towards 

 the aperture. This is one of the alated forms, remains of slight 

 bordering keels being visible here and there on the figured specimen, 

 and more perfectly on others. The tube was probably elliptical. 

 Dimensions : length 4f inches, breadth at aperture f th of an inch. 



This is the largest Dentalium known, exceeding D. grandis from 

 Japan in size by about an inch. Portions were found by me, during 

 my last visit to Folkestone, in the cast bed, where it apjpears to be 

 common. The figured specimen was found by Griffiths. 



The Figures 3 to 18 are drawn from specimens kindly lent by Mr. 

 Thomas Jesson, F.G.S. , late of Trinity College, Cambridge, and unite, 

 it appears to me, the following species from Cambridge. 



1. Crepidula gaultina, Buvignier. 



2. Calyptroea Coolcsonice, Seeley=:C. sanctce-criicis, Pict. etCamp. 



3. (?) Crepidula alta, Seeley. 



The depressed form (Figs. 3, 4, 5, 20) known as Crepidula 

 gaidtina, also found at Folkestone, is perhaps a young form, and, from 

 its flattened appearance, seems to have been fixed inside the apertures 

 of shells. Figure 20 is taken from the specimen originally described 

 by Seeley.^ The higher form known as Calyptrcea Coolcsonice, Seeley 

 (Figs. 6 to 19), may have been occasionally attached to the outside of 

 shells, as similar differences according with 'the position of attach- 

 ment may be seen in the forms of recent Calyptrceidce in the cases at 

 the British Museum. No character is discernible by which the 

 1 See Q. J. G. S., May, 1877, p. 201. 



