72 SUPPLEMENT TO THE CRAG MOLLUSCA. 



Rissoa eximia? Jeffreys. Supplement, Tab. VII, fig. 5. 



Rissoa eximia, Jeff. Ann. and Mag. Nat. Hist., n. s., vol. iv, p. 299, 1849. 

 Chemnitzia eximia, Forb. and Hani. Brit. Moll., vol. iv, p. 278, pi. xc, fig. 1, as 



Rissoa eximia. 

 Odostomia eximia, Jeff. Brit. Conch., vol. iv, p. 155, pi. Ixxv, fig. 4. 



Localities. Coralline Crag, Sutton. Living, Shetland Seas. 



The single specimen of this shell, which is represented in the figure as above, is all 

 that I have yet met with, and was found by myself in the Coralline Crag of Sutton. It is 

 strongly ribbed, and has three somewhat broad spiral strise on the lower part of the whorl, 

 in which respect there is a slight inaccuracy in the figure which shows but two such striae. 

 These strise crossing the ribs give rise to two rows of depressions or cavities between 

 them. The specimen is slightly worn. 



Rissoa semicostata, Woodward (non Mont). Crag Moll., vol. i, p. 102, Tab. XI, 



fig. 10, and also fig. 9 (as B. pulchetta). 



Localities. Red Crag, Butley, Sutton, and Kesgrave. Middle Glacial, Billockby. 



This shell was described by Woodward in his 'Geology of Norfolk ' (1833) under the 

 name of Turbosemicostatus, auctorum,hut the authors of the 'British Mollusca' and the author 

 of the c British Conchology' agree that Montagu's Turbo semicostatus is identical with B. striata 

 of Adams. As, however, I consider the Crag fossil to be distinct from any known recent 

 species, I have retained it under the name of semicostata, Woodward, that name being 

 unoccupied now that Adams' older name of striata is applied to the other (Montagu's) shell ; 

 the synonym Turbo semicostatus, Mont., given at page 102 of ' Crag Moll.,' being an error. 

 His son, Dr. Woodward, in the list of Norwich Crag shells in White's Directory of 

 Norfolk, refers this species to inconspicua, Alder ; but the Crag forms invariably have the 

 outer lip thickened and dentated within, which the recent inconspicua has not ; and if 

 this be a specific character, the two shells must be distinct. 



My identification of the shell shown in fig. 9, of Tab. XI, of Crag Moll., with 

 pulchetta, Phil., has been dissented from ; and in such dissent I agree, as I now believe 

 it to be the same as semicostata, Woodward ; I therefore unite these species under the 

 name of semicostata. Since the publication of the ' Crag Moll.' I have obtained three 

 specimens of the original semicostata, Woodward (fig. 10 of Tab. XI), from the Red Crag 

 of Butley, which may be synchronous with the Fluvio-marine Crag of Bramerton, 

 from which the shell shown in fig. 10 came. Those figured as pulchetta (fig. 9, a, b) 

 were, from what I consider to be, an older portion of the Red Crag, viz. that at Kesgrave 



