CHA.P. VII.] TRICHIXOPOLY DISTRICT — TRICHINOPOLY GROUP. 123 



of denudation since the commencement of the Trichinopoly epoch. 

 The Trichinopoly beds have indeed been denuded, but supposing that 

 they were originally continuous across, and that there has been no great 

 change in the relative levels of the country since the deposition of the 

 Trichinopoly beds, the present surface of the Ootatoor beds can be but 

 little lower than that on which these Trichinopolies were deposited. 



But, on the other hand, we have seen that the strike of the Trichino- 



Apparent general con- P^^^ ^^ds, and in many cases their dip also, 

 ormi y o group. ^^^^^ closely Coincide with that of the Ootatoor 



beds on which they rest ; a fact which would at first sight seem to 

 militate against the above conclusion. This is however, with few excep- 

 tions only, the case in that part of the formation which stretches North- 

 east and South-west, and is, I consider, to be sufficiently explained by 

 the general direction of the Trichinopoly coast line to the North of the 

 dislocation, having so far coincided with that of the Ootatoor coast 

 line, that the banks of sediment which constitute respectively the 

 Ootatoor and Trichinopoly groups, are also, for the most part, nearly 

 parallel. 



Along the Southern boundary, or in other words, at the head of the 

 bay formed by the Thutchuncoorchy ridge, we have seen that the 

 Trichinopoly deposits are very irregular, and consist of materials 

 derived in great part from the rocks of that ridge. The general dip of 

 the beds is to the East or North-east, and the opposite dip of the 



Bedding determined by ^eposits on the Eastern ridge of the basin prevails 

 irregxilar deposition. ^^ ^ ^^^^ ^^^^^ distance only from the boundary 



of the formation. This fact, even in the absence of other evidence, 

 would induce the suspicion that the inclination of the bedding is that 

 of original deposition ; and is not due to subsequent disturbance, a 

 view, the correctness of which is proved almost to demonstration, by 

 such clear instances on a smaller scale at that of the Paroovalapoor 

 outlier, and by the frequent local unconformities and irregular dips of 



