568 /. B. SCRIVENOR 



land when the denudation of the cover began, which was, as far as 

 we can tell, in late Mesozoic times (in the Archipelago Eocene 

 beds contain granite pebbles). To the east, the quartzite of the 

 Tahan massif and the granite of the East Coast CouUsse formed 

 another mass of superior resistance determining the extension of the 

 land in that direction. 



In my paper in the Geographical Review I sketched the history of 

 the Peninsula and Archipelago in Tertiary and recent times (pp. 353, 

 354). In Miocene times there is reason to believe that depression 

 converted the Archipelago into a few small islands and that later 

 "a gradual elevation occurred which ultimately united the whole 

 of the islands with the continent."' This depression must have 

 affected the area that is now British Malaya, and it was marine 

 denudation connected with this depression, then subaerial denuda- 

 tion when the uplift occurred, and marine denudation connected 

 with another depression in recent times, that revealed the true course 

 of the granite intrusions, and made the breaches in the Bintang 

 and Kledang CouKsses where the granite dips under the older 

 stratified rocks. In the case of the Kledang CouKsse, if the patch 

 of Tertiary rocks occurring in the gap is Miocene, the breach was 

 effected in Miocene times. 



The effect of marine denudation has been great. It is partic- 

 ularly noticeable in Johore, where the granite and other hills rise 

 like islands from a gently undulating plain, and in Perils and Kedah, 

 where some of the hills are even more striking in their resemblance 

 to islands. 



In the basin of the Perak River there is, above Kuala Kangsar, 

 evidence of the continuity of the granite between the coulisses. 

 The granite of the northern end of the Kledang Coulisse (No. 8) is 

 connected on the surface with that of No. 9 on the one hand and 

 that of No. 7 on the other. The granite of Gunong Perak also 

 (No. 3) is connected by comparatively low-lying outcrops with that 

 of the Bintang Coulisse, but elsewhere the granite outcrops of one 

 coulisse are separated from those on either side by stratified rocks. 



The granite outcrop connecting Gunong Perak with the Bintang 

 CouKsse strikes only a little to the north of Gunong Bintang, the 



' Dr. A. R. Wallace, Island Life, pp. 385, 386, 390. 



