embrace an area of about 500 square miles, the Barrakar coal 

 fields about 220 square miles and the Jheria coal fields about 

 200 square miles. The depth of some of the Ranigunj coal 

 seams is 70 to 80 ft. The Bengal carboniferous system 

 comes under what is called the Gondwana sytsem. Palaeozoic 

 animals were mostly marine. The fishes of this period were 

 characterised by bone armour-plates. The soils of this 

 system are indifferent, better than granite soils, but poorer 

 than basaltic and alluvial soils. Soils of the Old red sandstone 

 where limestones abound are rich, but they are scarcely re 

 presented in India. 



5th. The Mesozoic epoch. Air-breathing animals which first 

 made their appearance at the close of the Palaeozoic epoch, 

 appeared in abundance at the Mesozoic epoch. The lowest 

 group of this epoch is called the Triassic group (about 2,300 

 feet in maximum thickness ). The next higher is called the 

 Oolitic (about 4,500 ft. in maximum thickness) and the topmost 

 group is called the Cretaceous ( maximum thickness, 11,000 

 feet). Fossil remains of Labyrinthodon reptiles have been 

 discovered in the Damuda valley above the coal fields of the 

 Panchet hills. These are characteristic of the Triassic period. 

 They have been also discovered in the Central Provinces of 

 India: but Triassic rocks occur chiefly in the north-western 

 Himalayas, where they occur to the thickness of 1,000 fo 2,000 

 feet. The Oolitic group of rocks is subdivided into (i) 

 Liassic, (2) Jurassic and (3) Oolitic proper. Monstrous reptiles 

 (Icthyosaurus, Plesiosaurus and Pterodactyle) were the pre- 

 vailing animals of this period. The ammonite and belemnite 

 of the Himalayas are Oolitic. The shales and limestones of 

 the Himalayas are both Liassic and Ooltic. The Rajmahal 

 hills which abound in fossil plants are Jurassic. The 

 cretaceous system is not represented at all in Bengal, though 

 portions of the Nizam's dominion and of the Bombay Presi- 

 dency and also of Assam belong to this system. 



6th, The Neozoic epoch follows the palaeozoic, and at 



