GASTEROPODA. 147 



The beautiful specimen from which the figure above referred to was taken is 

 from the Museum of the Philosophical Institution, at York, obligingly sent me by 

 Mr. Charlesworth, for the purpose of being described. I think that there is little 

 doubt of this being identical with the recent Greenland species. Fine striee cover 

 the exterior, which are most visible near the suture and upon the base ; and the 

 apex, though not much eroded, has lost its outer coating. 



Sect. /3. OPERCULUM CALCAREOUS. 



11. Natica clausa. Broderip and Sotverby. Tab. XVI, fig. 2, a — b. 

 Natica clausa. Brod. and Soiv. Zool. Journ. No. 15, p. 372, 1829. 



— Gray. Zool. of Beechey's Voy. pi. 37, fig. 6, 34, f. 3. 



— Smith. Mem. "Wern. Soc. vol. viii, p. 55, pi. 1, fig. 16, 1838. 



— Gould. Invert, of Massachus. p. 238, fig. 167, 1841. 



— S. Wood. Catalogue 1842. 



Natica consolidata. Couthouy. Bost. Journ. Nat. Hist, xi, p. 89, pi. 3, fig. 14. 

 — septentrionalis. Mbller. Ind. Moll. Groen. p. 7, 1842. 



N. Testa globosd, imp erf or aid, laevigata ; anfractibus quinque ventricosioribus ; prope 

 ■vituram planulatis ; spird parum elatd; aperturd ovatd ; umbilico callo semiorbiculari, 

 complanato, prorsus obtecto. 



Shell globose, imperforate, smooth ; spire slightly elevated, with five convex 

 and rather tumid volutions, somewhat flattened on the upper part ; aperture ovate, 

 left lip with a semiorbicular and flattened callosity, completely covering the umbilicus- 



Axis, 1 inch nearly. 



Locality. Red Crag, Sutton. 



Mam. Crag, Bridlington. 



Recent, North of Europe, and Seas of Boreal America. 



This shell is rare as a Red Crag fossil. My cabinet contains but two specimens, 

 which, however, correspond precisely with the figure and description above referred 

 to, and I have no doubt of the identity. My specimens show a few traces of fine 

 stria?, where the outer covering has been removed, and there is the impression of 

 its calcareous lid on both sides of the aperture. It is very common in some of the 

 Swedish beds, as mentioned by Mr. Lyell, and is quoted by Professor E. Forbes, 

 in his { Report on the Existing Fauna and Flora of the British Isles,' as found at 

 Bridlington, though I have not seen a specimen from that locality. 



