MOOEE — ABXOEMAL SECONDAEY DEPOSITS. 



473 



such is also the case at Twerton, Weston, Saltford, Keynsham, and 

 other sections near Bath. It should be here noticed that, although 

 Ammonites angulatus and A. Buchlandi are supposed to represent 

 two distinct horizons, these sections are seen to have those shells in 

 common ; and often the former species will be found the prevailing 

 one, and attaining very large dimensions. 



The species found in the Camerton Gray Lias include : — 



Ammonites Bucklandi. 



Conybeari. 



angulatus. 



Turneri. 



I^Tautilus striatus. 

 Ostrea liassica. 

 Gryphffia incurva. 

 Pecten sublgevis. 

 Lima gigantea. 



Hermanni. 



duplicata. 



Plicatiila sarcinula. 



Avicula inffiquivalvis. 



Pinna. 



Pholadomja ambigua. 



E-hynchonella variabilis. 



Terebratula numismalis. 



punctata. 



Spirifera Walcottii. 

 Cidaris Edwardsii. 

 Pentacrinus tuberculatus. 

 Ophioderma. 

 Serpula strangulata. 

 Belemnites acutus. 



The Sjnrifer-banJc (a). — Lying upon the above beds we find an 

 indurated brownish marl characterized by the enormous number of 

 the Spirifera Walcottii it contains, some of which attain considerable 

 size for this genus, and are in a good state of preservation. Profes- 

 sor Quenstedt has, in his ' Der Jura ' recognized the presence of this 

 zone in Germany on the same horizon; and it is interesting to ob- 

 serve that, though it is but 6 inches in thickness, its continuity has 

 extended so far. The bed is of a somewhat conglomeratic character, 

 and contains numerous casts of FJioladomya ambigua, Myacites, Ger- 

 villia, and Ammonites semicostatus. 



The Foraminifera-zone (6). — This deposit, which is a laminated 

 blue clay of 8 feet in thickness, may be truly so denominated, since 

 I have found therein, for the first time in the Lias, not less than 

 twenty-eight species of these beautiful little shells. They will be 

 figured and described by my friend Mr. Brady, F.G.S., in the pub- 

 hcations of the Palseontographical Society. Although at the top of 

 the Lower Lias, many of the species are common to so-called Infra- 

 liassic beds ; with them are associated Plicatula spinosa, many En- 

 tomostraca, Pentacrinites, and fish- scales. 



Dentalina communis, D' Orb. 



interrupta, D' Orb. 



obliqua, Linn. 



obliquestriata, Eeuss. 



ovicula, D' Orb. 



pauperata, D' Orb, 



Cristellaria cultrata, Mont. 



crepidula, F. ^ M. 



costata, D' Orb. 



rotula, Lamk. 



Frondicularia complanata, U Orb. 



striatula, Eeuss. 



Involutina liassica, Jones. 

 Lingulina carinata, D' Orb. 



Marginulina raphanus, Linn. 



lituus, 2)' Orb. 



Nodosaria fascia, Linn. 



paucicostata, Rom. 



radicula, Ldnn. 



raphanus, Linn. 



raphanistrum, lAnn. 



Planularia Bronni. 



cornucopi^e, n. sp. 



longa, Cornuel. 



Trochammina incerta, P. ^ J. 

 Yaginulina legumen, Linn. 



" Iffivigata, Ebra. 



striata, Jy Orb. 



A blue limestone (c) with a laminated fracture, weathering yellow 



