340 ON THE TJPPEPv CHETAGEOTJS SERIES ETC. NEAR MONS. 



the Chalk ; (2) the interesting facts as to the possible formation of 

 the phosphates. 



Prof. Prestwigh remarked on the great interest of the paper, both 

 palseontologically and mineralogically. In the Paris basin and in 

 England the Chalk stops with the Senonian ; but here we have a 

 deposit which lies between the equivalents of the Maestricht Chalk 

 and the Senonian : he considered the evidence of its distinctive 

 character very satisfactory. 



In this country a few of the lower beds of the Chalk contain 

 phosphates, but they are of little importance. 



It was remarkable that the deposit should be confined to so small 

 a district. It was singular also that in the neighbourhood of 

 Mons not only should the Cretaceous series be more complete than 

 anywhere else, but also the Lower Tertiary series,. Even the 

 Quaternary beds show the same completeness. 



He considered the explanation as to the origin of the phosphates 

 interesting, and alluded to the beds of phosphate of lime at Quercy. 



Mr. Bauerman congratulated the Society on the valuable paper 

 they had heard from their distinguished Belgian correspondent, 

 whose example he hoped would stimulate contributions from other 

 foreign Members. He observed that there was very little to criticize. 

 He was disposed to agree with the Author's explanation as regards 

 origin — an instance of differential separation in weak acidulous 

 waters ; he quoted an analogous case in the Devonian limestones of 

 the Lahn valley, and the formation of staffelite. He further instanced 

 the deposits of Leadville, in which the less soluble substances had 

 been deposited as carbonates in the hollows of limestones below. 



Dr. Duncan admired the fossils, and observed that the species of 

 Gatopygus approximates more to the recent forms than does the 

 one from the Lower Chalk. 



Mr. Blaneord thought there might be some mistake as to the 

 quotation with reference to Perim and Aden, and suggested that the 

 locality where the periodical destruction of fish-life occurred was 

 the Malabar coast. 



Dr. Hicks had observed in Cambrian and Silurian beds an increase 

 of phosphates corresponding to an increase in animal remains. He 

 thought some of the results might be due to secondary causes. 



Dr. Woodward thought that possibly the phosphate in the Brown 

 Chalk of Ciply might not have been of contemporaneous origin, but 

 derived in some way from Tertiary beds above. 



Mr. HuDLESTON pointed out that this latter suggestion was 

 scarcely justified by the facts, since the Phosphatic Chalk was pro- 

 tected by the Tufaceous Chalk. He referred to the abundant remains 

 of fish and saurians in the bed as indicating, in part at least, the 

 source of the phosphate. 



The President, in conclusion, said the thanks of the Society were 

 due to Mrs. Prestwich for her excellent translation of the paper. 



