8 THIRD SUPPLEMENT TO THE CRAG MOLLUSCA. 



specific) which cannot be separated from the Crag and recent shell above referred to, but 

 of these some are given as fossils from deposits that are said to be purely of freshwater 

 origin, while others are given as from beds of purely marine origin. This species so 

 closely resembles some of those of Rissoa, that I do not know any character in the 

 testaceous part by which it can be separated from that genus. 



NODOSTOMA ORNATA, S. Wood, ' Crag Moll./ vol. i, p. 87, Tab. IX, fig. 6, as Odostomia 



simillima; 1st Sup., p. 64, as 0. ornata ; 3rd Sup., 

 Tab. I, fig. 13. 



Locality. Cor. Crag, Sutton. 



This pretty little shell was figured and described in the ' Crag Moll./' under the 

 name of Odostomia simittima, and was assigned to Montagu's species simillimus, which I 

 now consider was erroneous ; and in my first Supplement I assigned it as distinct, and 

 gave it the name ornata. The obscure tooth, stated in my first volume (p. 87) as 

 present upon the columella, is, I find, only a fragment of sand adhering to the columella, 

 while the aperture is more elongately ovate than in Odostomia, and of quite a different 

 form from that in Chemnitzia. My specimens were very few and somewhat variable, but 

 the species, I think, cannot be placed in the genus Odostomia, being apparently inter- 

 mediate between that genus and Eulima. I therefore propose to call it Nodostoma 1 from 

 its evident relationship with Odostomia^ but separated from it by its toothless character. 



The shell described by Montague is considered by the authors of ' Brit. Moll./ as well 

 as by the author of 'Brit. Conch./ to have been " a bleached and worn specimen" of 

 Chemnitzia rufa, Phil., and doubtfully British. The present figure is taken from a 

 single specimen that I have recently found, the shell being extremely rare. 



NODOSTOMA EULIMELLOIDES, S. Wood. 3rd Sup., Tab. I, fig. 14. 



Locality. Cor. Crag, Sutton. 



[Of the specimen figured as above, a sketch was made by my father for his intended 

 plate under this name ; and he appears to have intended to give it as a second species of 

 his new genus, Nodostoma, but he has left no other MS. respecting it beyond the above 

 specific name of eulimelloides. I have compared it with all the species of Eulima 

 described by him from the Crag, and it agrees with none satisfactorily. It comes nearest 

 to Ealima glabeHa, but the form of the mouth differs, the whorls are more cylindrical, 



, toothless, and oro/ua, mouth. 



