PREVIOUS ACCOUNTS. 7 
Pdrd limestone Rhatic. 
Lilang series Upper trias. 
Ruling series Carboniferous. 
Muth series Upper silurian. 
Bhabeh series Lower „ 
Each of the above series will be dealt with in detail in the chapters 
relating to the systems that thoy represent. 
Mr. Griesbach's chief object in visiting Spiti was to endeavour to 
remove certain discrepancies existing between 
(jRtESBACH. ' ° 
Stoliczka's account of the stratigraphy of Spiti 
and the conditions observed by him in the Kumaon and Garhwil 
Himalayas. His short account, although based on a somewhat rapid 
traverse, constitutes a distinct advance in our knowledge of the geology 
cf Spiti. 
As will be seen from his memoir, the chief points on which he 
differed from Stoliczka, were — 
(1) the age of the Muth quartzite (8)^ and underlying beds ; 
(2) the vertical extent of the carboniferous system ; 
(3) the age of Stoliczka's "■ Kuling series " ; 
(4) the presence or absence of beds of lower triassic age. 
With regard to the first point, subsequent work has shown that 
Stoliczka was correct in regarding the beds underlying the Muth 
quartzite as of silurian age, but no direct evidence as to the age of the 
quartzite itself has yet been found. 
With regard to the carboniferous system, Mr. Griesbach has shown 
that Stoliczka had erroneously included in it the " Productus shales," 
now known to be of permian age : these Stoliczka named the " Kuling 
shales," and included with them certain dark limestones found at Kul- 
ing and at Muth, and which are, in part at least, of carboniferous age. 
Mr. Griesbach was also the first to prove the existence of the lower 
trias in Spiti, Stoliczka having failed to notice it, though it appears that 
he subsequently came to the conclusion that beds of that age were to be 
found in the Himalayas. ^ 
1 This is the number employed by Mr. Griesbach in his list of formations. 
' Memoirs, G. S. 1., vol. V, p. 345. 
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