104 MOLLUSCA FROM THE CRAG. 



This may possibly be B. Montagui, Payr. (p. Ill, t. 5, f. 13-14), but our shell 

 appears to be less in size, and less ventricose. The elevated transverse ridges give 

 an apparent canal at the suture, and the outer lip is continuous with the inner one ; 

 at the base of the inner lip or columella the shell is slightly reflected. A shell 

 somewhat resembling this species, but larger, is not very uncommon in the London 

 clay, at Barton ; it is thickened within the outer lip, but has not the denticulations 

 characteristic of the Crag shell. Our figure represents the strise as rather too fine 

 and too numerous. 



7. Rissoa pulchella (?). Phil. Tab. XI, fig. 9, a— b. 



Rissoa pulchella. Phil. En. Moll. Sic. 1836, p. 155, t. 10, fig. 12. 



B. Testa ovato-conicd, ventricosd, injlatd, cr asset, subperforatd ; anfractibus quinque, 

 conveosis, tumid is, longitudinaliter costulatis ; costulis circiter quatiordecim, in anfractu 

 ultimo dimidiatis ; aperturd ovatd, spirant subaquante ; labro incrassato, intus denti- 

 culato (?). 



Shell ovato-conoidal, ventricose, thick, and strong, with five convex volutions, 

 longitudinally costated ; costas about fourteen, disappearing on the lower half of 

 the body whorl, with an ovate aperture, and a thickened outer lip, denticulated (?) 

 within. 



Axis, -^ of an inch. 



Locality. Red Crag, Sutton and Kesgrave. ? Recent, Mediterranean. 



My cabinet contains five specimens of what appears to be the same as the Medi- 

 terranean shell ; they have the inflated form and numerous ribs of M. Philippi's 

 figure, but there are the remains of stria? upon the base of our shell, and traces of 

 denticulations within the aperture, which do not appear to exist in the former. It is 

 larger and more ventricose than any of my specimens of B. semicostata, yet it is 

 possible it may be only a variety. The costse in our figure are rather too numerous, 

 and the volutions scarcely tumid enough. 



8. Rissoa confinis. S. Wood. Tab. XI, fig. 6, a — b. 



Rissoa confinis. S. Wood. Catalogue 1842. 



B. Testa ovato-conicd, subperforatd crassd ; apice obtuso ; anfractibus quinque, con- 

 'scuiisj suturisprofundis, longitudinaliter costatis; costis rectiusculis, elevatis, in anfractu 

 ultimo 9—12, transversim striatis, aut sulcatis ; aperturd subrotundd ; labro extus incras- 

 sato, intus dentato ; labio vix reflexo, umbilico parvo. 



Shell small, ovato-conoidal, perforate, thick and strong, with a rather obtuse 

 apex ; volutions five, convex ; suture distinct and deep, longitudinally costated ; 

 costse 9 — 12, nearly erect, elevated, covered with depressed transverse striae ; aper- 

 ture suborbicular ; outer lip thickened, dentated within ; peristome continuous ; the 

 left lip slightly reflected, partly covering a small umbilicus. 



Axis, yjj of an inch. 



Locality. Cor. Crag, Sutton. 



