64. SUPPLEMENT TO THE CRAG MOLLUSCA. 
Opostomia uNrDENTATA, Montagu. Appendix, p. 317, Tab. XXXL, fig. 11. 
Localities. Red Crag, Walton. Middle Glacial, Billockby P 
In addition to the solitary specimen from Walton, mentioned p. 317 of Appendix, a 
specimen has occurred in the Middle Glacial sand at Billockby that seems referable to 
this species, but it is not sufficiently perfect to be free from doubt. 
Oposromra oBLIQuA? Alder. Supplement, Tab. IV, fig. 24. 
OpostomiA oBLIQua, Alder. Ann. and Mag. Nat. Hist., vol. xiii, p. 327, pl. vi, fig. 12. 
Locality. Cor. Crag, Sutton. 
A single specimen, obtained by me from the Cor. Crag of Sutton, is represented m 
the above figure, and referred with doubt to the above species ; it is, I believe, a young 
individual, and the form not very well shown. Mr. A. Bell has since my engraving was 
made found a full-grown specimen, which I would rather have figured. 
Opostomia? ornata, S. Wood. Crag. Moll. vol. i, p. 87, Tab. IX, fig. 6 (as 
O. siemalima). 
This shell is, I now believe, quite distinct from O. simzllima of Montague, to which | 
assigned it with doubt in the ‘ Crag Moll.’ I am unable to refer the Crag shell to any 
species known to myself, either British or European. In my ‘Catalogue of Crag Mol- 
lusca,’ 1842, it was called Rissoa? costellata, but as the name costellata is already 
appropriated to another shell, 1 propose to call it ornafa. It is so aberrant a form of 
Odostomia that I had intended to erect a new genus for it, but I have thought it better 
to leave that task to some future author, when some allied forms that can be grouped with 
it may have been discovered. 
ODOSTOMIA ALBELLA, Lovén. 
Since the figures for this Supplement were engraved Mr. Robert Bell has sent me 
from the Coralline Crag of Sutton a specimen with the name a/bel/a attached, but I have 
not yet had the opportunity of comparing it with Lovén’s shell. 
Genus. —EULIMENE. 
In the ‘ Crag Mollusca,’ vol. i, p. 109, two Red Crag shells are referred to the genus Palu- 
destrina, viz. P. pendula and P. terrebellata. The first of these was described im my Cata- 
logue of 1842 as Hulima pendula. n external shape both these shells resemble some of the 
