GASTEROPODA. 11 



Cassidaria bicatenata, /. Sow. Crag Moll., vol. i, p. 27, Tab. IV, fig. 5. 



Localities. Cor. Crag, Ramsholt and near Orford. Red Crag, Sutton, Bawdsey, 

 Felixstowe, and Waldringfield. Fluvio-marine Crag, near Norwich ? 



Var. ecatenata. Supplement, Tab. VI, fig. 1, a. 



Locality. Cor. Crag, near Orford. 



The figure represents a specimen of Cassidaria from Mr. Cavell's cabinet, with a 

 more elongated form than what I have had previously figured as bicatenata, and it is free 

 from the double chain-like ornament upon the upper part of the volution. It approaches 

 very near to C. Tyrrhena, Chemn., but it is, I believe, specifically distinct. It is from 

 the Coralline Crag at Orford. I have also found the general form of bicatenata with its 

 two rows of nodules or catenae in the Cor. Crag at Ramsholt. Our present specimen 

 differs also in the ornamentation, not having the small intermediate line between the 

 ridges. 



Fig. 1, b, Tab. VI, represents a small specimen in Mr. Canham's cabinet of 

 Cassidaria bicatenata from the Red Crag at Waldringfield, which I have had figured to 

 show that the thickened margin to the outer lip was in this case formed before the 

 shell had attained to half of its usual size. The present specimen having had its aperture 

 and anterior termination enveloped, may perhaps have had its natural growth checked 

 and so became adult, though of so small a size ; but this does not necessarily follow, 

 because the thickening of the lip in this group of Mollusca is by no means an indication 

 of the adult condition, for in the recent forms of Cassis this thickening of the lip may 

 sometimes be seen to have occurred two or three times in the growth of the animal. 

 This species is included in the list of shells from the neighbourhood of Norwich obtained 

 by Sir C. Lyell in 1838, and identified for him by the late Mr. G. Sowerby and myself 

 ('Mag. Nat. Hist.,' n. s., vol. iii, p. 329). I can therefore scarcely doubt its being a 

 genuine Norwich Crag shell, though it does not appear to have been found of late years 

 in the neighbourhood of Norwich. 



'o J 



Nassa granifera, Dujardin. Supplement, Tab. VI, fig. 11. 



Buccinum graniferum, Dujctrd. Geol. Tr. France, vol. ii, pt. 2, pi. 20, figs. 11, 12. 

 Nassa granifera, A. Bell. Ann. and Mag. Nat. Hist., May, 1871. 



Axis, -j^tbs of an inch, nearly. 



Localities. Coralline Crag, Gedgrave {A. Bell), Sutton [S. Wood). Red Crag, Sutton 

 (S. Wood). 



