92 Transactions. 



sidered as related to the present orographic features. These are, no doubt, 

 a very late development, as demanded by McKay and by Cotton. The 

 failure to appreciate this point thoroughly no doubt influenced Hutton, 

 and to some extent Morgan (1916, p. 28), in attempting to fix the position 

 of the shore-line of the Tertiary sea in that region. 



Since we maintain the conformity of the two limestones, and since we 

 can suggest no other horizon where a physical break occurs in the series 

 under consideration, our present contention involves the recognition of 

 the stratigraphical conformity of beds in the lower part of the sequence 

 containing Cretaceous fossils with those higher containing Tertiary fossils. 

 (For the latest pronouncement on the Cretaceous age of the lower members 

 of the series see Trechmann, 1917, p. 295.) In our opinion the beds 

 with Cretaceous fossils are definitely Cretaceous, and those higher up with 

 Tertiary forms are Tertiary. The anomaly is accounted for by the slow 

 and continuous deposition of the beds, so that when the period of deposition 

 commenced the time was Cretaceous, and when it closed it was Tertiary, 

 judging by European standards of geological time. The earlier part of this 

 period was marked by slow depression of the land, with a corresponding 

 change in the nature of the deposits (see Speight, 1917, pp. 350-51). 

 During the time of maximum submergence the greensands and limestones 

 were deposited, and as the sea-bottom was raised a reversal of the order 

 took place with slight minor oscillations. When one considers the small 

 area of land which was probably in existence above sea-level in the vicinity 

 of the region under consideration, the slow rate of deposition can be readily 

 understood. Thus during this long period of submergence of the area the 

 local fauna had time to change from a Cretaceous to a Tertiary facies. 



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