376 Revieivs — Geology of India. 



In a prefatory note the Director of the Survey explains why this 

 new edition was unavoidably delayed, and why he " accepted Mr. 

 K. D. Oldham's offer to prepare a fresh issue " of the book " accordant 

 with our progressive Survey of the Empire." 



In this new edition, instead of describing the geological features 

 and conditions of separate districts on a geographical plan, the new 

 arrangement takes the formations of the two (peninsular and extra- 

 peninsular) regions together in their chronological order. Thus the 

 two tables at pages 82 and 83 of the Geol. Mag. 1880, have to be 

 taken together. Some corrected determinations of the true age of 

 certain groups of strata allow of this new plan being adopted with 

 advantage. For those parts of the country where the Survey has 

 not been able to add any particulars, the text " has been allowed to 

 stand practically as in the original publication " ; but revised and 

 condensed. Some alterations, on account of advancing knowledge, 

 have been made where necessary. " In the Table of Contents, the 

 portions in which the First Edition has been taken as the basis of 

 the text are distinguished by a different type from that which 

 refers to portions which are new or have been entirely re-written." 

 Judging from the appearance of the new among the old headings, 

 the proportion of the new to the old matter is about 9 to 22. 



The first paragraph in Chapter I. is cei'tainly re-written, but is 

 rather longer than at page ii. in the first edition. The rest of the 

 chapter confines itself mainly to the Physical Geography, without 

 so much introductory and general classificatory matter as was given 

 in 1879. Chapter II. shows that the metamorphic and crystalline 

 rocks are now better known. The non-fossiliferous older sedi- 

 mentary rocks are still referred to some "Transition" series or 

 systems (Chap. III.) 



The " older palfeozoic " (Vindhyan, or Cambro-Silurian, for the 

 tipper, and Cuddapah for the lower) systems, both in the peninsular 

 and the extra-peninsular areas, and including indications of Devonian 

 in Thibet, and Silurian in Burma, are dealt with in Chapters IV. 

 and V. The Carboniferous and Triassic rocks of extra-peninsular 

 India (the Salt-Range, Ruling, Simla, Kashmir, etc.), with possible 

 glacial beds, come into successional order here (Chap. VI.). The 

 important Gondwana system succeeds (Chapters VII. and VIII.) ; 

 with the Coal-beds of Damuda, Raniganj, etc., with their interesting 

 fossil flora, fishes, and reptiles. The correlation of these formations 

 with others in Australia and South Africa is carefully reproduced. 

 The Lower Gondwana comprises stages from Carboniferous to Trias; 

 and the Upper Gondwana is Jurassic. The marine Jurassic strata 

 of Cutch, Western Eajputana, Spiti, Hazara, etc., are found in 

 Chap. IX. ; and the marine Cretaceous beds of the Peninsula, in 

 Chap. X. The affinities of the latter with extra- Indian Cretaceous 

 formations is of considerable interest ; so also the relation of the 

 great Trappean formation of the Deccan to the same series and to 

 the Eocene volcanic rocks of the Himalaya, somewhat condensed 

 from the first edition. The extra-peninsular Cretaceous rocks are 

 briefly treated, with some new notes, in Chap. XIL 



