﻿BENGUET PETROGRAPHY. 



237 



reported to me by men who are in their own fields considered good 

 observers. It is needless to say that before such a startling announcement 

 as giaciation in this region can be made much more work in the area 

 should be carried on, and this is proposed for the early part of 1908. 

 The bearing of the possible discovery of giaciation upon problems of 

 tropical animal and plant distribution, would of course be profound. 



I have made use of the new method of Dr. Eugene Wright in the 

 determination of feldspars and have found it highly satisfactory. It 

 will be recalled that this method makes use of a series of standardized 

 oils composed of definite proportions of cedar, cinnamon and clove oil. 



I wish here to acknowledge some assistance rendered by my colleague, 

 Mr. H. G. Ferguson, in the preparation of the tables in this paper. 



Bibliography of Benguet petrography . 



1878 — Druschc, R. Yon. Fragmente zu einer Geologie der Insel Luzon (Philip- 



pinen), mit einem Anhange iiber die Foraminifera der Tertiaren Thone 



von Luzon, von Felix Karrer. Vienna, Gerold's Sohn. 

 1881 — Oebbelc, K. Beitriige zur Petrographie der Philippinen und der Palau- 



Inseln in Ncues Jahrbuch f. Mineralogie, etc. Beilage, Band I, Stuttgart, 



Koch. 

 1893 — Abella y Casariego, Enrique. Terremotos experimentados en la isla de 



Luzon durante los meses de etc. Manila Chofre 8°, 110 pp. 1 diagram 



and map. 

 1893 — Abella and others. Estudio descriptivo de algunos manantiales minerales 



de Filipinas etc. Manila, Chofre, 8°, pp. 150. 



List of Benguet rocks described in this paper. 



Series 

 No. 



Field 

 No. 



Name. 



Locality. 



Page. 



1 

 2 

 3 



4 

 5 

 6 

 7 

 8 

 9 



10 

 • 11 

 12 

 13 

 14 

 15 

 16 

 17 

 18 



4 

 12 

 153 

 13 

 16 

 116 

 106 

 107 

 101 

 102 

 132 

 126 

 23 

 124 

 103 

 150 

 108 



Quartz diorite _ __ 



Peterson's Mill 



1 

 238 

 238 

 242 

 240 

 240 

 243 

 244 

 245 

 245 

 246 

 246 

 247 

 247 

 249 

 248 

 241 

 249 

 249 



.. do, . .. .. _. . _ . 



Batuaan. __ 



. .do - - 



Unknown _ __ _ 



Diorite — _ _ - -- 



Gold Creek, near Kelly's 



do _ _. _ __ __ __ 



do 



Dacite 



Bua-Antamok, and Gold Creek 



Big cut, Benguet road ... 



Hypersthene augite andesite _. 

 Angite andesite . _________ 



Near provincial governor's house.. 

 Trinidad road 



Andesitic tuff __ 



_do 





Andesite porphyry 



Benguet road below Colgon's 



Murphy's Creek 



__ _do - _ - _ . 



Antamok _ 



do 



Antamok Igorot workings _ 





Trinidad road .... 



Graywacke 



Unknown ... ... 



Foraminiferal limestone . 



Ridge in Naguilian road 



Limestone — _ 



Benguet road above "zigzag" 





