UPPER GREENS AND AND CHLORITIC MARL. 



375 



cretosus, P. Beaveri, Lima sp., P. Galliennei (?) may eventually 

 be found to characterize different zones, while the entire fauna of 

 the malm rock is different from that of the chert and rag beds. 



I would propose, also, that the 50 feet of sands included in the 

 Upper Greensand by Mr. Bristow, and more recently by Dr. Barrois, 

 should be referred to the Gault, taking the well-marked band of 

 chert boulders with Chelonia &c. as the true base of the Upper 

 Greensand. 



I also suggest, with some diffidence, that remains of island floras 

 and faunas exist in the marine deposits of those Greensands, as 

 evidenced by a freshwater Tortoise and Cycadeous plants, the former 

 authoritatively stated by Prof. Owen to be a freshwater reptile, 

 while the leaf-stalks and stems of tropical plants speak for them- 

 selves. 



Dr. Barrois's division of the Upper Greensand into two zones 

 is misleading, as the fossils are confined to such narrow limits. I 

 would suggest, in place of this, several zones in the upper cherts 

 identified by characteristic Pectinidae, which are the best- preserved 

 of the Mollusca, the fauna of the Malm rock being clearly separated 

 from that of the Rag. 



Mr. Jukes-Browne's zone of Seaphites cec/ualis is inaccurate. 

 20 feet higher up in the Chalk Marl S. cequalis is abundant ; in the 

 Chloritic it is hardly ever found. Turrilites Morrisii is, on the 

 other hand, characteristic of this horizon. 



The band of phosphatic nodules with crushed Pecten as'per de- 

 serves attention. This species of Pecten is certainly not properly 

 a Chloritic-Marl fossil ; yet it only occurs in the peculiarly crushed 

 state in this formation ; it is never found in the Greensand proper 

 in the Isle of Wight. 



Discussion. 



Mr. H. G. Eordham stated that between Ballard Hole and Pun- 

 field Cove the phosphatic nodules are scattered through the Chloritic 

 Marl, and not confined to its base, and that no broken shells of 

 Pecten asper occur at that point. He further remarked that the 

 author gave the thickness of the Chloritic Marl as 6 feet, i. e. greater 

 than previous authors. 



The President stated that the new Ammonite mentioned by the 

 author seemed to be intermediate between A. rostratus and A. 

 auritus, but nearer to the former. Pecten asper had not previously 

 been noticed above the Upper Greensand. He referred to the great 

 value of Dr. Barrois's labours in connexion with the English Chalk. 



Eev. J. F. Blake thought that the beds with Ammonites inflatus 

 belonged to the Upper Gault, and not to the Greensand. 



Mr. J. Starkie Gardner thought that, as species of Pecten and 

 Lima have often a long range, their value for characterizing horizons 

 in the Cretaceous was doubtful. 



Mr. De Bance stated that Pecten asper in Dorsetshire never 

 occurs above the Greensand. He agreed with Mr. Blakj in re- 

 garding the zone of Ammonites inflatus as Upper Gault. 



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