PROF. E. FORBES ON LOWER GREENSAND FOSSILS. 351 



Loc. Atherfield. 



Note. Pterocera moreausiana D'Orbigny, T. C. pi. 211. f. 1 — 2. comes very 

 near this species. 



136. Pterocera Fittoni. Sp. nov. (pi. iv. f. 6.) 



P. testa brevi, crassa, anfractibus 6, spiraliter striatis, supe- 

 rioribus 3-carinatis, ultimo 8-carinatis, carinis duabus majo- 

 ribus, crenulatis, labro quadridigitato, digitis linearibus, 

 arcuatis. 



Lon. 1 T 8 ^ unc. Lat. ? 



Body of the shell ovate, ventricose with a spire of 5 whorls, all 

 finely striated and ribbed spirally. The ribs on the upper whorls 

 are few and nearly equal ; those on the body whorl are numerous 

 and of various dimensions ; two corresponding to the anterior 

 digitations of the lip are very strong, prominent, and crenated. 

 A strong rib also runs between them. The lip is much dilated 

 and is furnished with 4 digitations, the two anterior free, the two 

 posterior attached, that above to the spire, and the lower one to the 

 canal. The superior digitation is very long, linear, and curved, 

 and exceeds the spire by half its length. The canal is also linear 

 and curved. In all the specimens the anterior digitations are im- 

 perfect. 



Loc. Atherfield. 



Note. This species is nearly allied to Pterocera retusa and Pterocera moreau- 

 siana. From the former it is distinguished by the crenated keels of the body 

 whorl, their number and size ; from the latter by the same characters, and by 

 the long linear superior digitation. 



137. Cerithium Neocomiense. (PI. iv. fig. 8.) Cerithium Neoco- 

 miensc and C. Beaudouini D'Orbigny. 



C. testa conica, turrita, anfractibus 9 — 11, convexis, cari- 

 natis, transverse undulato-striatis, carinis laevibus. 



Lon. T 8 2 ; lat. 0^ unc. 



Shell turreted, lanceolate, whorls carinated, the keels sharp and 

 regular, usually only one on the upper whorls, and two or three on 

 the lowermost, never crenated, crossed by undulating stria? of 

 growth, and sometimes obscure spiral striae. Canal very short. A 

 very beautiful species, variable in proportions and degree of cari- 

 nation. The British specimens are usually intermediate between 

 the variety figured by D'Orbigny under the name of Cerithium 

 Neocomiense (T. C. pi. 232. fig. 8 — 9.), and that named by him 

 Cerithium Beaudouini, and figured under the name of Rostellaria 

 pyramidalis in his plate 206. fig. 7 — 8. Judging from the figure, 

 his Cerithium tectum, a gault species (T. C. pi. 230. f. 4 — 6.) does 

 not appear to be more than a variety. 



Loc. Atherfield. (In the Cracker bed.) 



