DEVONIAN SYSTEM. 33 
Chapter IV. 
DEVONIAN (?), CARBONIFEROUS AND PERMIAN. 
It is a curious fact that although rocks of devonian age had long 
, been known to occur on either side of the Indian 
Recent discovery of 
devonian beds in Empire, yet, until quite recently, none had been 
found in the intervening area. During the 
field season of 1899- 1900, Mr. T. D. La Touche, assisted by Mr. 
P. N. Datta, made the first discovery of devonian fossils, in the 
Northern Shan States, and during the subsequent season, Mr. La 
Touche succeeded in obtaining a large collection of well-preserved and 
thoroughly characteristic species. Almost simultaneously with IVtr. 
and in the Hindu '-'^ Touche's discoveries in the most easterly part 
Kush. Qf ^j^g Empire, the collection of devonian fossils 
mentioned in the last chapter was made by Captain Gurdon, in the 
Hindu Kush, thus bringing the devonian beds almost to the confines 
of the Himalayas, but as yet no fossils which could be unequivocally 
referred to that system have been discovered in this great mountain 
range. 
In the Niti area and in Spiti, Mr. Griesbach has described a " hard, 
dark, concretionary coral limestone," varying in thickness from 650 to 
nearly 1,000 feet, which he believed to be of devonian age. This 
correlation, however, is not based on the evidence of fossils, but depends 
on the fact that the limestone overlies the red quartzite, regarded by 
him as of upper silurian age, and underlies the "redcrinoid limestone" 
which he ascribed to the carboniferous system. From the section 
south of Muth, in Spiti, he describes his devonian system as " a thick- 
ness of from 700 to 800 feet of a very dark, hard limestone, concre- 
tionary in parts, alternating with dark, splintery shales." ^ This can 
only represent the limestone series, described in the last chapter, 
which overlies the red silurian quartzite and has now been found to 
P 
* Memoirs, G. S. I., vol. XXIII, p. 21A. 
C 33 ) 
