1854.] Proceedings of the Asiatic Society. 619 



instances the lower beds are partially made up of the disintegrated particles 

 of the trap itself, mechanically re-arranged. The evidence is quite conclu- 

 sive that there have been successive flows of matter in a state of fusion, 

 during a long continued period, during the intervals of which mechanical 

 deposits of sand and mud, often highly charged with vegetable remains 

 took place. 



These remains of plants are often remarkably well preserved, and occur 

 so associated, that we mnst consider the whole series of beds, notwithstand- 

 ing its' interruption by the intercalation of the great masses of foreign mat- 

 ter, as forming one group or formation belonging, generally, to the same 

 geological epoch as the coal-bearing rocks of the Ranigunj district. 



The true age of these rocks is one of the most interesting questions of 

 Indian Geology ; and anything tending to throw light on it, is of great 

 geological interest. Unfortunately in the Bengal coal-field no animal remains 

 have as yet been found to aid in its solution. And no true or well defined 

 horizon or datum line has been established from which the position of these 

 rocks in the general series can be ascertained. I have already, in a previous 

 number of this Journal, expressed my own opinion on this question; but it 

 may be as well to point out the state of the case more fully. 



In the coal-fields of India, numerous remains of fossil plants are found 

 referable to genera, which to European geologists are known only to occur 

 in rocks of a more recent date than the true carboniferous epoch. Asso- 

 ciated with these are other genera not hitherto found at all in European 

 rocks, but occurring plentifully in this country, and also in Australia. Now 

 it is well known to every geologist, that the remains of plants alone furnish 

 exceedingly poor evidence on which to base any conclusions with regard to 

 the age of the rocks in which they occur. And this being the case, it is 

 important to find, if possible, fossils belonging to the animal kingdom in 

 connexion with them. Now in Australia, associated with beds containing 

 fossil plants specifically identical with those found in the Indian coal-fields, 

 occur other beds rich in animal remains, of a well marked type, which type 

 represents a period (geological) corresponding to the lower carboniferous 

 group of Europe. It was at first supposed that the beds containing the 

 fossil plants occurred above, and formed a distinct group from the shelly 

 beds; but the observation of all the most trustworthy witnesses negatives 

 this. And in Australia, so far as our present evidence goes, it must, I think 

 be conceded, that the same fossil plants, which in India characterize the 

 coal-yielding beds, occur associated with abundant remains of shells, which 

 must be considered of the carboniferous epoch of European geology. But 

 the question is by no means so easily solved : for passing into Western 

 India, we find associated with identically the same plants, as occur with those 



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