352 On the age of the Coal strata in Central India, [No. 4, 



Hitherto my remarks have been confined to the carbonaceous 

 strata and laminated sandstone of Central India. In now including 

 the coal measures of Bengal in my comparison, I must bespeak 

 indulgence, as I have personally examined none of the strata or 

 fossils of that part of India, and must depend wholly on the descrip- 

 tions and a few figures that have already been published. 



By "coal measures of Bengal" of course I do not understand 

 those on the N. or N. E. of Calcutta, some of which doubtless 

 belong to a Tertiary age ; but I mean those on the W. and N. W. 

 of the Indian Metropolis, of which the strata in the Damiida basin 

 may serve as a specimen. 



These strata, I consider to be the same as what we have in the 

 north of this province, and therefore, if my previous reasoning has 

 been sound, they also are to be regarded as Jurassic. The grounds 

 of my identification are 1st, similarity in organic remains, and 2nd 

 in geological position. 



1. Similarity of organic remains. — In the bituminous shales of the 

 Mahadeva we have the following Bengal fossil plants: Tryzygia 

 speciosa, Vertebraria indica, and a species of Phyllotheca, a fragment 

 of which is figured by Dr. McClelland as JPoxcites minor. Geol. 

 Jurn. Tab. XVI. f. 4. In the carbonaceous shales of Umret, besides, 

 the jPhyllotheca now alluded to, another stem, but unfurrowed, 

 which seems to resemble McClelland's Poxites murieata. Tab. XIV. 

 f. 6. In the laminated sandstone of Kampti, in addition to Verte- 

 braria and the two Poacites as above, Tceniopteris, perhaps of the 

 same species as at Rajmahal, and McClelland's Pecopteris affinis. 

 Tab. XIII. f. 11 b. y which in our specimen, is seen to be a well mark- 

 ed species with a tripinnate frond. 



In all these localities, the genus Gloscopteris abounds, but it is so 

 difiicult to represent in a figure its minutely anastomosing vena- 

 tion, that nothing but a comparison of specimens side by side 

 would warrant the identification of species. However, there is 

 little fear of any of the Bengal ones failing to find a match among 

 some of ours, as from the sandstone and coal shale, we must have 

 about twelve species in all, many of them very perfect and in the 

 height of fructification. While we seem to have outstripped North 

 Eastern India in Cyclopteris and several other vegetable remains. 



