120 MOLLUSCA FROM THE CRAG. 



2. LiTTORINA (?) SUBOPERTA. /. Soio. Tab. X, fig. 13. 



ViviPARA SUBOPERTA. /. Soiv. Min. Concli. t. 31, fig. 6, 1813. 

 LiTTORINA SUBOPERTA. Morrts. Cat. of Brit. Foss. p. 149. 



— Nyst. Coq. foss. de Belg. p. 388, pi. 37, fig. 1, 1844. 



Z. Testa elongato-conicd, crassd, ntyosci; apice aciito ; anfradibus anpcstis, convexi- 

 nsculis ; ultimo ad hasim suhangulato ; aperturd ovatd; columelld callosd. 



Shell elongato-conical, thick, and rugose, with an elevated spire, and acute apex ; 

 whorls depressed, elongated, subangulated at the base of the volution ; aperture ovate, 

 slightly contracted above and below ; columella callous, left lip spreading over the 

 umbilicus. 



Axis, I of an inch. 



Locality. Red Crag, Sutton, Walton, Newbourn, and Bawdsey. 



Specimens of this species may be found in numerous localities, but all which I have 

 seen are in a mutilated and altered condition, having been more or less rubbed and 

 broken. The shell is thick and strong, and generally rugose, except in those specimens 

 that have been nibbed or eroded. The inner lip is rather extended, forming a small 

 callosity, and covering the umbilicus. 



FossARUs,* Phil 1841. 

 Phasianema. S. Wood, 1842. 



Gen. Char. " Shell semiglobose, umbilicate, with an entire semicircular aperture, 

 left or inner lip without folds (edentulous), never callous ; umbilicus open ; outer lip 

 shaqj, smooth within ; operculum semiorbicular, corneous, not spiral." 



Such are the characters given for a genus of shells by M. Philippi (in En. Moll. 

 Sic. 1844, p. 147), and which he states to have been previously published in 'Archiv 

 f. Naturgesch,' 1841. This is the revival of the name Fossar, used by Adanson, in his 

 excellent work upon the Mollusca of Senegal in 1 757, and which species M. Philippi 

 considers as the type of the genus. When compiling my Catalogue, I was not aware 

 of the existence of this genus ; the name of Phasianema there proposed must of course 

 give place to that by M. Philippi. 



* Since the above has been in the press, I have discovered, in Mr. Gray's List of Genera, the name of 

 Forsar, Gray, for this genus, with a date of 1840. 



