ODOSTOMIA. 135 



coasts. Fossil in the Clyde beds (Crosskey) , and in the 

 glacial and post-glacial formations in Norway at the re- 

 spective heights of 400^60 feet and 50-100 feet (Sars). 

 Its foreign distribution is doubtful, because this species 

 has not been satisfactorily identified by some continental 

 authors. For instance, Petit has recorded it from the 

 Gulf of Lyons on the authority of M. Martin, and Ve- 

 rany from Nice ; but in both these cases I ascertained 

 that O. pallida had been mistaken for the present species. 

 I must for the same reason question the locality of Al- 

 geria given by M. Weinkauff. The. following, however, 

 may be relied on : — Norway as far north as Hammer- 

 fest, in 10-50 f. (Sars) ; Stromstad, Bohuslan, on an 

 oyster from 12 f. (Rubenson, fide Malm) ; and Loire- 

 Inferieure (Cailliaud) . 



From Mr. Clark's account the animal differs little 

 from that of O. acuta. The shell may be distinguished 

 from that and other allied species by its squarish mouth 

 and nearly rectangular base, and from O. conspicua by 

 its smaller size, colour, and smooth throat. I found a 

 living specimen which had lost all the upper part of the 

 spire. 



It is the Sabancea Montaguana of Leach, taking his 

 synonymy as my guide : his description is so vague and 

 almost unintelligible, that it would serve for any of the 

 smooth species. 



14. O. turri'ta*, Hanley. 



O. turrita, Hani, in Proc. Zool. Soc. pt. xii. p. 18. O. unidentata, var. ?, 

 F. & H. iii. p. 267, pi. xcv. f. 9. 



Body white, with a bluish tinge, and transparent, covered 

 with exceedingly minute granules, which give the surface 

 (especially the foot) a frosted appearance: snout narrow, rounded 



* Turrcted. 



