﻿434 ROCKS OF PULATJ TJBIN AND PTJLATT NAN AS. [Aug. I9IO r 



(3) A pyroxene-microgranite and porphyry on Pulau Ubin, and 

 a rock at Changi, having the mineral constitution of an amphibole- 

 vogesite, are described. Their relations to the other rocks are not 

 clear. 



(4) The dacite-tuffs of Pulau Nanas contain fragments of granite 

 which must be pre-Carboniferous, and are referable in point of age- 

 to the granite of Amboyna. 



(5) The fragments of granite, and perhaps pebbles of schorl- 

 rock, are the only evidence found in the Malay Peninsula as yet of 

 pre-Carboniferous rocks. 



