47 



PART III. 



General Considerations. 



Having completed the purely lithological and stratigraphical des- 

 cription of the rocks of both fields, and having alluded to the physical 

 features, the special topography, and the drainage of each, I shall now 

 notice the several questions of geological interest which are deducible 

 from the evidence collected during the examination of the valley, and 

 finally give a summary of the resources of each field. 



The facts which have been recorded in the foregoing papqr, and 

 the memoirs of the Geological Survey (treating of the Damuda valley), 

 relating to the composition, structure, and organic contents of the coal- 

 measure rocks and the strata associated with them, enable us, with 

 some degree of accuracy, to speculate upon the probable physical con- 

 ditions under which these were deposited. 



The most important consideration at the outset is the determination 

 of the organic contents, for they teach us what the conditions of life 

 were, and yield satisfactory data for the correlation of the different rock 

 systems. 



The great preponderance of fossil plants over other organic forms 

 in the Talchir, Damuda, and Panchet formations makes the name of the 

 great ' plant-bearing series', as applied to these rocks, a very appropriate 

 one ; and in order to show that it is deserved, I append a synopsis of 

 the principal fossil remains which have been discovered in the Damuda 

 valley. 



TalcMr series. — Glossopteris, Cyclopteris, a few stems, and some 

 seeds. No distinct fauna. 



Damuda series. — 



Barakar group : Glossopteris, Verfeiraria, ZeugopJiyllites, trunks of 

 tiees. No distinct fauna. 



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