Oeologtcal Society. 337 



February 2, 1881.— llobert Etheridge, Esq., E.R.S., 

 President, in the Chair. 



The following communications were read : — 



1. "On the Coralliferous Series of Sind, and its Connexion with 

 the last Upheaval of the Himalayas." By Prof. P. Martin Duncan, 

 M.B. Lond., F.R.8., E.G.S. 



This communication is the result of the author's study and de- 

 scription of the fossil corals of Sind, undertaken at the request of 

 the Geological Survey of India. The history of the researches in 

 the geology of the Tertiary deposits of Western Sind was noticed in 

 relation to a statement made some years since by the author and 

 Mr. H. M. Jenkins, E.G.S., that there was more than one Tertiary 

 series there, in opposition to both D'Archiac and Haime. 



After a brief description of the geology of the Kliirthar and 

 Laki ranges of hills, which were called Hala Mountains by the 

 French geologists, the succession of the stratigraphical series demon- 

 strated by the Survey under Blanford and Fedclen was given, and the 

 author proceeded to discuss the peculiarities of the six coral faunas 

 of the area, and to argue upon the conditions which prevailed during 

 their existence. A transitional fauna, neither Cretaceous nor Eocene, 

 underlies a trap ; to the trap succeeds a great development of Num- 

 mulitic beds, the Ranikot series, containing corals, some of which 

 are gigantic representatives of European Nummulitic forms. A third 

 fauna, the Khirthar, succeeds, and a fourth, Khirthar-Nari, which 

 Avas a reef-building one ; and a fifth, the Nari, is included in the 

 Oligoceue age. An important Miocene coralliferous series (the Gaj) 

 is on the toji of all. These faunas above the trap are jN^ummulitic, 

 Oligocene, and Miocene in age ; and in the first two, European forms 

 -which are confined to definite horizons are scattered indefinitely in 

 a vertical range of many thousands of feet. The corals grew in 

 shallow seas ; but most of them were not massive limestone-builders, 

 but there were occasional fringing reefs, or rather banks of com- 

 pound forms, which assisted in the development of limestones. Many 

 genera of corals which elsewhere are massive, are pedunculate in 

 Sind; and the number of species of the family Fungida^ is consider- 

 able. There are also alliances with the Eocene coral fauna of the 

 West Indies. 



The depth of the coralliferous series and the intercalated unfossi- 

 liferous sandstones &c. is, according to the Survey, 14,000 feet, 

 without counting an estimated 6000 feet of unfossiliferous strata in 

 one particular group. The subsidence has therefore been vast, but 

 not always continuous. 



After noticing the numbers of genera and species in this grand 

 series of coral faunas and the remarkable distinctness of each, the 

 author proceeded to discuss the second part of his subject. When 

 President of the Society, he had stated, in his Anniversary Address 

 for 1878, that he was not convinced of the truth of the theory of 

 the Geological Survey of India regarding the Pliocene age of the last 

 Himalayan upheaval. The considerations arising from the position 



