NOTICE. 



The Sixth Vokime of The Memoirs of the Geological Survey 

 OF India, now issued, will be found to contain papers descriptive of large 

 areas of country in different parts of India. These relate chiefly to 

 Western India, but there are also detailed descriptions and maps of two 

 of the smaller detached Coal-fields of Bengal. Full osteolog-ical details 

 are also given of the interesting remains of Frogs, long known to 

 Geologists as occurring near Bombay ; and of which the Survey has been 

 fortunate in obtaining some well preserved specimens recently exposed by 

 engineering works ruidertaken in that locality for reclamation pru^poses. 



The present Volume gives a description of the Geological Structure 

 of about sixty thousand square miles of country, — an area larger than 

 that of all England and Wales. It is not intended to convey the idea 

 that our examination of this immense area has been sufiiciently detailed 

 or close to justify its being considered final — (this would have been 

 impossible within the time which has been devoted to it) , — but I believe 

 that this examination has been carried out as carefully, and recorded in as 

 full detail, as was practicable with the very imperfect topographical maps 

 which we had at our disposal. The nature and value of these will be 

 found noticed in the several papers, now published. 



The structure of quite as extensive an area of country adjoining that 

 herein described will be noticed in the next volume of the Memoirs, now 

 in preparation. 



Calcutta, ^ THOMAS OLDHAM, 



December 1868. J Sujidt., Geological Survey of India, 



