﻿IGO 



SUPPLEMENT TO THE CRAG MOLLUSCA. 



Some small specimens of a Corbula, which I have referred as above, were sent to me 

 intermixed with C. striata, by Mr. Reeve, from Bramerton, and I have also some from 

 Easton Bavent, and from the small patch of fossiliferous pebbles at Ditchingham. 

 Some nearly perfect specimens have also occurred in the Middle Glacial of Hopton. 

 These specimens are smooth, but that is usually the case with all those which can be readily 

 referred to C. striata; the principal distinction, as pointed out by the American authors, 

 is the nearly equal size of the valves of the present species, and the more inequilateral 

 form of the valve, the posterior side being elongated. The recent shell is said to be 

 abundant on] the Coast of Georgia and East Florida. The specimen figured is from 

 Bramerton. 



Corbula striata, Walk, and Bop. Crag Moll., vol. ii, p. 274, Tab. XXX, fig. 3. 



Localities. Cor. Crag passim. Red Crag, Walton, Sutton, Bawdsey, and Butley, 

 Fluvio-marine Crag passim. Chillesford bed passim. Lower Glacial, Weybourne, 

 Belaugh, and Rackheath. Middle Glacial, Hopton and Billockby. Post-glacial, March, 

 Hunstanton, and Kelsea Hill (Jeffreys), Nar Brickearth (Rose). 



This shell is profuse in the Coralline, but somewhat rare in the Red, Crag. In the 

 Chillesford bed it seems to be rare where this is in a Fluvio-marine condition, and 

 commoner as it becomes more marine ; but I have not met with it from the most 

 marine development of the bed, viz. that at Chillesford. In the Lower Glacial sands it 

 is common, and in the Middle Glacial very abundant ; but I have not seen it from 

 Bridlington. It does not seem common at any of the Post-glacial localities. Fig. 4, 

 Tab. XXX, of ' Crag Moll.,' is the representation of a shell which I referred to C. rosea, 

 but which I now believe to be a transverse variety of striata. 



I have retained the name of striata for this shell, conceiving the right of priority to 

 be with Walker and Boys, who figured the recent shell with that name in 1787, whereas 

 the name of gibba was given to it by Olivi in 1792. Lamarck at a later date described 

 a Paris basin fossil with the name of Corbula striata, and this M. Deshayes has 

 ('An. sans Vert, du Bas. de Paris,' T. 1, p. 221), I think, very properly called 

 C. Lamarchii, restoring to the recent shell the name of striata. The name striata was also 

 adopted by the late Dr. Fleming in his ' Hist, of Brit. Animals,' a very able work at the 

 time it was published, and for which the author has never received the credit he 

 deserved. 



Corbulomya complanata, J. Soiv. Crag Moll., vol. ii, p. 275, Tab. XXX, fig. 2. 

 In considering, as I did in the ' Crag Moll.,' the Paris basin shell to be the same 



