Chap. Ill] sub-himalayan series — subathu group. 75 



fossil evidence, I have left them as one group, for the following reasons : — 

 firstly, the threefold characters I have noted in the sediment are 

 perfectly transitional by interstratification, the change in the nature of 

 the deposition being gradual, from what we may suppose to be tranquil 

 deposition in moderately deep water to tranquil deposition in shallow 

 water. There is scarcely even a small pebble to be found throughout 

 the whole formation, as represented in this area. And, secondly, there is 

 much evidence for the supposition that, in one direction at least, the 

 limitation of the basin of deposition was the same for the lower as for 

 the upper beds. 



It will be shown, with much probability, that a period of most exten- 

 As a Sub-Himalayan sive denudation, consequent on considerable disturb- 

 group " ances in this region of the Himalayan system, 



intervened before the deposition of the rocks which here follow next to 

 the Subathu group. Yet I rank this group as the lowest of a series of 

 formations, under the same general name Sub-Himalayan, because this 

 group seems to have had an original limit of deposition approximately 

 coincident with what has been ever since a limit of deposition, with 

 what has been throughout a zone of disturbance connected with the 

 Himalayan system of elevation, and with a zone of, what may now 

 be emphatically called, Sub-Himalayan rocks. Great as the interval in 

 time must have been between the deposition of the Subathu group and 

 that of the succeeding groups of the series, at least in the eastern part 

 of the district, we find in the upper portion of the Subathu rocks the 

 very characters most distinctive of this great Tertiary series, as a whole ■ 

 the massive clays and sandstones of Dugshai and Kasaoli being unmis- 

 takeable congeners of the rocks of the Nahun and the Sivalik Hills. 

 The three following statements express the general relations of the 

 Relations to Lower Sub-Himalayan roc k s t0 tri0se of the L ower 

 Himalayan rocks. Himalaya. First, the Subathu beds, the sub- 



group of undoubted nummulitic age, rest upon a deeply denuded surface 



