INFERIOR OOLITE AMMONITE-ZONES. 



159 



considerable numbers, added to the abundance of" long spiral univalves belonging to the 

 genera Chemnitzia and Nerinaa, which are known to " nestle in Coral-formations, together 

 with the indirect evidence of a superabundance of Brachiopoda^ added to the litho- 

 logical character of the marl itself, which appears to be the product of Coral-mud and 

 other reef debris, leads to the conclusion that the Oolite-marl is a portion of a Jurassic 

 Coral-bank." ^ 



MOLLUSCA. 



Chemnitzia procera, Beslong. 

 Nerineea gracilis, Lye. 

 Natica adducta, Phil. 

 Trochotomia calyx, Lye. 

 Trochus monilitectus, Phil. 

 Monodonta laevigata, Sow. 

 Natica macrostoma, Roem. 



Terebratula submaxillata, Davids. 



— fimbria. Sow. 



— carinata, Lamk. 



Stomechinns germinans, Phil, 

 Pedina Smithii, Forb. 



Mytilus imbricatus. Sow. 

 Lima punctata, Phil. 

 — Pontonis, Lye. 

 Area cancellata, Phil. 

 Lucina Wrightii, Oppel. 

 Myopsis punctata, Buek. 

 Ceroraya concentrica, Sow. 



Brachiopoua. 



Rhynchonella Lycetti, Davids. 



— concinna, Sow. 



— angulata. Sow. 



ECHINODERMATA. 



Pseudodiadema depressum, Agaas, 

 Acrosalenia Lycetti, Wright. 



No. 13. Thin hard bands of Oolitic Limestone, without fossils, eighteen inches. 



No. 14. Thin beds of fine-grained Oolitic Limestone, four feet six inches. 



No. 15. Hard Bubbly Oolite-marl. — This occurs in broken masses five feet thick. 



These three beds are well exposed in a small escarpment on the western slope of 

 the hill, near the large Freestone Quarry. They contain few fossils, and the rock is much 

 shaken. 



No. 16. The Loioer Freestone attains a considerable thickness in Cleeve Hill, and 

 has long been extensively raised there for building-purposes. It is divisible into two 

 terraces, the upper of which contains the best beds of stone. The rock is a fine-grained 

 thick-bedded oolitic limestone, remarkably free from organic remains and ferruginous 

 stains. The upper terrace is twenty-six feet in thickness. 



No. 17. The Loioer Freestone. — The lower terrace is exposed on the western 

 escarpment of the hill. The rock is nut equal in quality to the beds in the upper 

 terrace, and it is therefore not now worked for building-stone. Its exact thickness I 

 have not ascertained, but I estimate it at forty feet. 



1 "Wright, " On the Sub-divisions of the Inferior Oolite," 'Quart. Journ. of the Geol. Soc.,' vol. xvi, 

 p. 13, 1860. 



