68 REPORT — 18GG. 



(which have an earthy fraeturo, and often contain remains of shells), and lumps of 

 hardened clay. The nodules contain a much larger percentage of alumina than 

 those of the' Cambridge Greeusand. Tliis would indicate that the phosphatic 

 nodules had been formed of clay soaked in decomposing animal and vegetable 

 matter, since the alumina could not be derived from animal or vegetable sources. 

 The nodules are often covered with perforations, which Mr. A. Wanklyn discovered 

 to be the work of small biralccf, of which he obtained several species. 



The remains of organic life found in this deposit exist in different states of miner- 

 alization. Some are coeval with the deposition of the bed, whilst others have been 

 washed out of preexisting deposits. 



Of vegetable remains are found :— 



1. Large masses of silicilied wood, resembling those found in the Pm'beck. 



2. Small pieces of wood, mineralized with phosphoric acid, and often bored by a 

 nev7 species of Pholas, which I have named " Pholas Dallasii." 



3. Cone of Cycadacean, from the Wealden. 

 Of remains of animal origin we find ; — 



Rolled bones and teeth of reptiles and fishes, also shells of mollusca existing in 

 two distinct conditions, viz., phosphatic casts and ferruginous shells. 



The phosphatic casts of shells are generally so much worn, that it is impossible 

 to identify their species ^vitll precision. Their general aspect resembles those of 

 the Kimmeridge and Oxford clays. They consist of casts of BhtpiclioneUa ; Car- 

 dium, Area, P/ioIaduiiii/a, &c. ; I'lcurvtomaria, Cliemnitzia, Katica, &c. Also two or 

 three species of Ammonites occur, of which Atnnioni/es hiplcx is foiuid in great 

 abundance. Several of the Ammonites retain tlieir nacreous lustre ; phragmoconea 

 of large Belemnites are also found. 



Part of the ferruginous shells also ha^■e been derived from extraneous sources, 

 and among these is Gryphma dilutata. 



The rest of the ferruginous shells are of the age of the Lower Greeusand. 

 Amongst these there are fomid — 



Waldh eim ia Tamarindus, 



celtica. 



Terehratida depressa. - 



Pleurotomaria De Lahaysit, 



Pecten jRobinaldimis, 



Ostrea macroptera, 



Exogyra conica. 



Myacites ptUcata. 



Sphcera Sedywickii, n. sp. 

 Ferruginous casts of a shell resembling a " Po^na," and other mollusca have been 

 also foimd. 



The remains of fishes seem to be principally derived from the Kimmeridge Clay, 

 The following species have been also found in the Kimmeridge Clay at Ely : — 



Sph<erodus yigas (palate teeth), ^ery common. 



Pycnodii^, sp. (palate teeth). 



Gyrodus, sp. (palate). 



Asteracanthm ornatissimm (dorsal spines), common. 



Leptctcanthus (spine). 



Hybodus, sp. (spines and teeth). 



Sphenonchus. 



Lepidotus, sp. (scales). 



Pscnnmodus retictdatus (palate teeth), very common. 



JEdaphodon, sp. 



The remains of reptiles are chiefly rolled bones and teeth of Pksiosmmis and 

 Ichthyosaums] and remains of Pliosaurm, which reptile is characteristic of the 

 Upper and Middle Oolites, occur in considerable quantities. 



Some teeth of Crocodilian character are found here as well as at Ely, probably 

 belonging to a species of Quenstedt's genus Dakosauri(s. Waterwom remains of the 

 Jgumiodon, and pieces of shelly limestone containing Cyrenas, have been derived 



