334 Royal Geological Society of Ireland. 



Prof. Morris mentioned the occurrence of similar deposits near "Wissant, on the 

 coast of France, and near Calne, in Wiltshire. He called attention to the extremely 

 quiet natui-e of the sea in which the phosphatic bed been deposited, and observed on 

 the existence in recent times on certain sea-shores of ooze containing a large amount 

 of phosphatic matter. 



Mr. Fisher, in reply, stated that he had in his paper but slightly touched on the 

 sources of derivation of the phosphate of lime ; but as to the possibility of that sub- 

 stance being localized and derived in large quantity from fish, he pointed out that the 

 principal manure of modern times, guano, was derived from this source. He alluded 

 to the possibility of some process of dialysis having contributed to the segregation of 

 the phosphate. He disputed the identity of the nodules in the Gault and in the 

 chloritic marl at Cambridge. As to the character of the fossils, he regarded it as the 

 same as that to be found in a thin band at the base of the Chalk in parts of Hants and 

 Dorset. 



Mr. Sollas had examined sections of the fossils from the Cambridge beds under the 

 microscope, but had failed to find the canals or tuberculated spicules characteristic of 

 Alcyonaria. He had, however, in the sand found numerous indisputable sponge 

 spicules. He had, moreover, found in sections of the coprolites spicules such as were 

 regarded by Dr. Bowerbank as characteristic of sponges. He hoped however, to 

 recur to the subject. Both Mr. Fisher and himself concurred in removing these 

 nodules from the category of concretions, and placing them under the head of organic 

 fossils. The transported blocks in the beds bear evidence of glacial action, and he 

 considered had been brought from Scotland or Scandinavia. He thought that some 

 portion of the phosphatic matter was derived from the decomposition of the volcanic 

 rocks north of Lammermuir, which were rich in this substance, and of which rocks he 

 had found fragments near Cambridge. He considered that, under certain circum- 

 stances, the phosphatic matter present in water would combine with animal and 

 mineral matter, aud hoped at some future time to offer some remarks on this subject 

 to the Society. 



EoTAL Geological Society of Ireland. — June 12, 1872. — 

 Prof. Macalister, M.D., President, in the Chair. 



Prof. Hull, F.E.S., exhibited two slices, of Chalk from County 

 Antrim, showing under the microscope its essentially Foraminiferous 

 structure. On comparing the forms with those in Ehrenberg's 

 MiJcrogeologie, Prof. Traquair and the author were able to identify at 

 least five genera, namely Botalia, Textularia, Planulina, Nodosaria, 

 and Globigerina — this last named being, as in the Atlantic mud, the 

 most abundant; and, in fact, constituting the greater part of the 

 mass of the rock. The cross-section of the spine of an Echinus, and 

 other forms of doubtful affinities, were also observed. The shells 

 were nearly all preserved in calcite, and bound together by im- 

 palpable carbonate of lime. The slices were made by Mr. Jordan, of 

 the Museum of Practical Geology. 



Mr. Hull called attention to the fact that the Foraminifera of the 

 Chalk of the north of Ireland had scarcely received any attention 

 from paleeontologists. This, he considered, might be partly at- 

 tributed to the unusually indurated character of the stone, which 

 rendered it almost impossible to extract Foraminifers by washing. 

 This quality, however, was favourable to the preparation of thin 

 slices for microscopic examination ; and Professor Eupert Jones had 

 kindly undertaken to examine slices of the Antrim Chalk for com- 

 parison with those forms now under investigation by himself and 

 Mr. Parker. 



