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DIKNKR : TRIAS OV THE HIMALAYAS. 
The Lower Trias seems to be developed in a facies of dark limestones 
and shales in the lower, and of liglit grey limestones in the upper, divi- 
sion. In the Lissar valley this group reaches an entire thickness of 80 
to 100 feet, according to Griesbach (Central Himalayas, 1. c, p. 175). 
Palaeontologically those two divisions are well characterised by two 
different associations of fossils, which can be easily distinguished among 
tlie collections of those two learned authors, which were made on the 
crest of a ridge separating the Lissar and Dharma valleys. The presence 
of the lower division, including equivalents of the Otoceras and Meeko- 
ceras beds, is clearly proved by the following species : — 
Pseudomonotis {Claraia) Grieabachi Bittn. 
Xenodiscus himalayanus Griesb. 
,, cf. rofyula Waag. 
Opliiceras SaJamtala Dieii. 
Propli/chites Lypicus Krafft. 
Meekoceras boreale Dien. 
,, dubium Krafft. 
Asyidites Vidarbhu Dien. 
The upper division of the Lower Trias (Hedenstrtemia beds) is indi- 
cated by Xenodiscus Purusha Dien. 
d. Byans. 
The Lower Trias of Byans differs considerably from that of Johar, 
Painkhanda and Spiti. 
According to the notes of F. H. Smith (1899) and A. v. Krafft (1900), 
it is represented by a mass of chocolate limestone attaining about 150 
feet in thickness. This limestone passes by interstratification into the 
underlying Productus, or Kuling, shales. No fossils have been found in 
those passage- beds by Smith, but near the base of the compact, choco- 
late-coloured limestone both A. v. Krafft and F. H. Smith have collected 
numerous fossils in a sandy rock near Jolinka and Kuti. They point 
distinctly to the lower division of the Lower Trias. 
One species, Ophicerus cf. serpentinum Dien., is characteristic of the 
Otoceras stage. The rest are chiefly elements of the Meekoceras fauna, 
namely : — 
Meekoceras boreale Dien. 
,, dubium Krafft. 
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