DALING AND DARJILING SERIES. 43 



The greater portion of the area coloured pink is occupied by true 



gneiss, but the rock very frequently passes into 

 Lithology of gneiss. 



mica-schist, or into a variety intermediate between 



the two ; a felspathic mica-schist or gneissose schist. Bands of quartzite 

 occur but rarely, and hornblendic rocks are extremely uncommon and 

 in beds of insignificant thickness. The actual gneiss itself is generally 

 composed of translucent, colorless or grey quartz, white opaque felspar, 

 and dark brown and silvery mica ; it varies in texture from a fine- 

 grained to a moderately coarse rock, lenticular layers of different degrees 

 of coarseness being commonly interbanded. Almost the only accessory 

 minerals are kyanite, schorl aud garnet, the last mentioned of which is 

 sometimes disseminated through the mica-schist in coarse crystals oj 

 considerable size. The gneiss is always well foliated, and the layers are 

 not unfrequently wavy, the length of the waves varying from a few 

 inches to as many feet. This is the incipient stage of the sharp crump- 

 lings on a small scale, which are also common, by which the layers 

 are folded completely back on each other. 



I have not observed any granite in the Darjiling district, but 



Dr. Hooker describes the gneiss further north, 

 Absence of granite. 



near Kanchinjinga, as penetrated by numerous 



veins, the intrusive rock being sometimes fine-grained, in other cases 



largely crystallized and composed of " pearly white prisms of felspar, 



glassy quartz, and milk-white flat plates of mica, with occasional large 



crystals of tourmaline.""* This gneiss may be different from that of 



Darjiling, and correspond with Dr. Stoliczka's ( central gueiss' of the 



north-western Himalayas, which is penetrated by innumerable granite 



veins, and which he considers to be the oldest formation of that area 



and of pre- silurian age. 



I have shown that the junction of the Daling beds and the Damudas 



_,,. , t., ..,. is a natural one. It follows from this and the 



Daling and Darjiling 



series post-Damuda. above considerations respecting the superposition 



* Himalayan Journals, Vol. I, p. 251. 



( 43 ) 



