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SUPPLEMENT TO THE CRAG MOLLUSCA. 



Discina fallens, S. JFood. Supplement, Tab. XI, fig. 6. 



Discina Norvegica? S. JVood. Ann. and Mag. Nat. Hist., p. 253, 184C. 

 Orbicula lamellosa, Davidson. Brit. Tert. Brach., p. 7, 1852. 



Diam. — ? 



Locality. Coralline Crag, Sutton. 



The only specimens of this genus that have yet, so far as I know, been found in the 

 Crag are the one figured by Mr. Davidson from my collection in the British Museum, 

 and now figured as above, and another which I have since obtained, but of which the 

 exterior is wholly concealed by Cellepora. The recent shell called Orbicula lamellosa, to 

 which this fossil was referred by Mr. Davidson, is a native of the coast of Peru, but he 

 now considers that the reference of the Crag shell to this species was incorrect. 



A shell was obtained by Professor King at the depth of 1 240 fathoms in Lat. 52° 8' N., 

 and 15° 30' W. Long, (about 140 miles from land), which he described under the name 

 of Discina Atlantica. Mr. Jeffreys, in his list of Cor. Crag shells accompanying Mr. 

 Prestwich's paper, has referred my Crag shell to this species of Professor King. 



I have had some correspondence with Mr. Davidson respecting this Crag fossil, and 

 he is of opinion with me that it cannot be referred either to Orbicula lamellosa or to 

 Discina Atlantica, and that, while placing it in the genus Discina, it ought, for the present 

 at least, to have a distinct specific appellation. As Mr. Davidson originally described the 

 Crag shell, I proposed to him that he should give it a new name and point out what he 

 considered were the characters for specific separation, but he has left it to me to do this. 

 The features which, so far as its meagre condition allow me to speak, distinguish the 

 Crag shell from Atlantica consist in its less conical form, and in the more excentric position 

 of its apex. I have, therefore, provisionally called it by the above name, fallens. 



Lingula Dumortieri, Nyst. Supplement, Tab. XI, fig. 1 a — c. 



Lingula Dumontieri, Nyst. In Davidson's Mon. Brit. Tert. Brach., p. 5, 1852. 



Length, 1 inch ; breadth, \ inch. 



Localities. Coralline Crag, Sutton, and near Orford. 



Fragments of this shell are not particularly rare at Sutton, but I have been unable 

 as yet to obtain a specimen that has not been more or less mutilated. A similar remark 

 is made by M. Nyst respecting the same species found at Antwerp. 



The genus Lingula has been generally considered as an inhabitant of tropical or sub- 



