now living in the British Seas. 345 



gine. Dr. J. E. Gray gave another name (Limnopsis) to this 

 genus in 1840; but this may have originated in a lapsus 

 calami. 



The first conchologist who pointed out the difference between 

 Limopsis and Pectunculus, although he retained both in the old 

 Linncan genus Area, was Brocehi, who, in his ' Conchiologia 

 Fossile Subapennina' (1814, vol. ii. p. 485, tab. 11. f. 9), de- 

 scribed the species which I have now noticed as an inhabitant 

 of the British seas. His description and remarks are, as usual, 

 most excellent. This species (L. aurita) is not uncommon in the 

 Coralline Crag at Gedgravc ; and Mr. Searlcs Wood suspected 

 that it may have lived on to the Red Crag period, as his cabinet 

 contained a specimen, but much water-worn, from that forma- 

 tion. 



It is quite impossible to distinguish, as species, the recent shells 

 dredged in our own northern sea from those found in the Coral- 

 line Crag ; and I believe other species of Limopsis arc also de- 

 rived from Tertiary forms, but that they have not been hitherto 

 identified with them. 



The recent species appear to be six in number, viz. : — 



1. multistriata, Forskal; Red Sea. 



2. Belckeri, Adams & Reeve. This is perhaps the Pectunculus 



(jranulatus of Lamarck, an Eocene fossil from Grignon. 



3. munita, Philippi ; from the Sicilian and Calabrian Tertiaries. 



Probably the same as two recent specimens in the British 

 Museum, the locality of which is unknown : or it may be a 

 variety of the next. 



4. aurita, Brocehi (Trigonocalia sublavigata, Nyst) ; Shetland. 



The single valve of a Limopsis, dredged by Mr. M 'Andrew 

 on the coast of Norway, and now in the British Museum, 

 appears to belong to a variety of this species, and to differ 

 from the typical form only in the inside of the front margin 

 being notched — a character which is not uncommon in va- 

 rieties of Astarte sulcata and A. triangularis. Prof. Sars, 

 in his Catalogue of 1857, regards this last specimen as be- 

 longing to L. munita; while Danielssen, in his more recent 

 work published in 1859, refers it to the Pectunculus \njg- 

 mceus of Philippi. 



5. cancellata, Reeve; not uncommon on shells of a variety of 



Phorus Indicus, but apparently fossil. 



6. pcllucida, Jeffreys ; dredged off Guernsey. A minute species ; 



but, although quite distinct from the young of any other 

 species, it requires further investigation in regard to its true 

 position. 



Although the particulars which I am enabled to give of the 



