312 GEOLOGICAL RELATIONS OP THE ROCK SYSTEMS 



sub-divisions. In the lowermost of these groups he had included those 

 beds which more recent research has shewn to belong to the Talcheer 

 group. But, independently of this, his classification is a very sound 

 one, and the several successive groups are well marked and distinct.* 



I am as yet quite unprepared to say how far these sub-divisions 

 may be truly represented in other districts in India. Three distinct 

 groups are given by the Messrs. Blanford, as composing this Damuda 

 system in Talcheer (a) and in Nagpur also, Messrs. Hislop and Hunter 

 have proposed sub-divisions of the rocks, which they suppose to belong all 

 to one formation. We may, however, safely say that much still remains 

 to be done in the details of the geology of those districts, before any safe 

 attempt can be made at establishing the parallelism of these minor 

 groups. 



Upper Damuda. — In the report (b) by Mr. Jos. G. Medlicott, given 

 above, it will be seen that he has distinguished from the true Damuda 

 rocks, a series of beds separated from them by a marked break in physi- 

 cal continuity, but still linked to them by a continuance of the same 

 o-eneral conditions, or character of the deposits. To these he has given 

 the name Upper Damuda. 



* The valued labours of my colleague Mr. William T. Blanford, who is at present 

 engaged in the re-examination of this important Coal-field, have proved the existence of 

 an unconformity, or of a physical break between each of these sub-div.sions. So far as 

 the fossil evidence has as yet been examined, there is no proof of any great break in 

 time. A considerable difference in the flora of each group of rocks may be traced, but 

 this difference would appear to be due rather to varying conditions of the surface, than 

 to any great change indicative of a considerable lapse of time, inasmuch as several 

 plants pass from one group to the other. 



Since the above was sent to press, Mr. Blanford has been rewarded by the most 

 valuable discovery of reptilian remains in the uppermost group of this field. These have 

 only been found within the last few days, and have not as yet been examined. But the 

 fact of the occurrence of animal remains of any kind is in the highest degree interesting, 

 as no trace of any thing but vegetable relics had previously been seen in these rocks. 

 And as I have already remarked, it is well known how untrustworthy their evidence is, 

 in determining the relative age of the rocks in which they occur. 



(a) Memoir of Geol.'Surv. of India Vol. I. p. 46. 



(6) Ditto ditto Vol. II. p. 176 &e. 



