368 MR. J. B. SCRIVENOR ON THE [June I9I3,. 



western coast of Sumatra, through Java, and so up to the Philip- 

 pines. Perhaps some of the rocks of Western Porneo described 

 by Wing Easton, 1 some of those of Central Porneo described by 

 Dr. Molengraaff, 2 and the Middle Oolite of Sarawak described by 

 Mr. P. P. Newton and myself 3 will ultimately be connected with 

 the Malayan Gondwana rocks. They show characteristics of 

 deposition in a deeper sea ; but that is only to be expected, seeing 

 that once we turn eastwards we are receding from the site of the- 

 coast of Gondwanaland. 



The geological history of the Malay Peninsula, as traced in 

 this paper, may be summarized as follows : — 



During the Mesozoic Era earth-movements took place in a 

 part of the crust which is to-day the site of the Peninsula. These 

 movements resulted in the formation of two large anticlinal folds.. 

 The folding admitted of the intrusion of two masses of granite, 

 and the intrusion was accompanied by faulting of the rocks in the 

 folds and by ' magmatic stoping ' on a large scale. 



The rocks affected by the folding are the calcareous Paub Series- 

 and the Malayan Gondwana rocks, resting unconformably on the 

 Paub Series and in many places faulted down against it. 



The palaeontological evidence afforded by small collections from 

 the Paub Series cannot be reconciled with the field-evidence. No 

 fixed horizon has been discovered in these rocks, which may be 

 Carboniferous or Permo-Carboniferous. Associated with the Paub 

 Series are volcanic rocks that are evidence of contemporaneous 

 submarine eruptions. The eruptions continued into later times. 



At the base of the Gondwana rocks are glacial deposits, which 

 may be referred to the same horizon as the late Palaeozoic glacial 

 deposits of Peninsular India, the Salt Pange, Australia, and 

 South Africa ; but this horizon cannot be defined exactly in the 

 terms of the European sequence. Its presence shows that the- 

 Paub Series must be older than the Produchis Peds of the Salt 

 Pange, or equivalent to the shales below the boulder-bed in the- 

 trans-Indus section of the Salt Pange. 



The glacial deposits are succeeded by littoral deposits, and a long 

 way east of the former a Phsetic horizon : has been described in 

 the latter by Mr. P. P. Newton, and named by him Myophorian 

 Sandstone. To account for the apparent discrepancy in age between 

 the climatic horizon afforded by the glacial deposits and the 

 Myophorian Sandstone, an hypothesis has been adopted to the effect 

 that the Malayan Gondwana rocks were deposited on the Gond- 

 wanaland coast-line as it moved slowly eastwards, probably with 

 many checks and oscillations. 



1 'Geologie ernes Teiles von West-Borneo ' Jaarb. Mijnw. Nederl. O.-I. 

 vol. xxxiii (1904) Wetensch. Gedeelte. 



2 ' Geological Explorations in Central Borneo ' London 1902. 



3 Geol. Mag. dec. 4, vol. iv (1897) pp. 407-15 ; also ' Keport on the Geology 

 of Sarawak' published in the F.M.S. Government Gazette, 1904. 



