PART 4.] IFaagen: Geographical distrilmtioii of fossil organisms in India. 279 
They are brown or grey, sandy or earthy, often oolitic, more rarely compact and 
thick-bedded, and contain innumerable fossils, which can in great part be identi¬ 
fied with species from the Kossener beds. The occurrence of Nerinseas and large 
Belemnites in these beds is remarkable. In two places, on the Parang pass and the 
Tagling pass, Stoliczka noticed in the uppermost beds of these limestones, which 
appeared to be of blue grey colour and compact, some species common to the 
Hierlatz beds, according to which the limestones would have been considered as 
liassic. This is the only case in which in the whole vast region of India liassic 
fossils are mentioned with confidence. The Tagling limestone is covered bj'’ hard¬ 
ened shales with Posidonomyas ; they form the transition to the well-known Spiti 
shales which long since furnished Ammonites to the European collections. It has 
not yet been attempted to carry out a closer sub-division of the.se beds ; but it is at 
any rate quite certain that the greatest number of the fossils were derived from 
a bed which corresiionds in age with the uppermost jui'a of Europe (the Kimmer- 
idge and Tithonian groups), and that Stoliezka’s views as to their age, and 
also many of his determinations of species, must be considered as erroneous. 
The thickness of the Spiti .shales hardly ever exceeds 500 feet, but is general¬ 
ly less. Above them follow sandstones (Gieumal sandstones) which contain in 
Spiti but a very meagre fauna, and in which farther to the westward I observed 
Trigonias resembling those of the Oomia group in Kachh. These sandstones 
conclude the Jurassic formation. The cretaceous series is represented in Spiti 
by the Chikkim limestones and Chikkim shales, the former of which enclose frag¬ 
ments of the shells of Rndistoe. 
The distribution of the secondary rocks northward of the first crystalline zone 
eastward from Ngari-Khorsum is but very little known. Strachey mentions 
Jurassic Ammonites from Eastern Nepal; but this statement has not been confirmed 
recently. Jura.ssic Ammonites have, however, been cited with greater certainty 
from the immediate neighbourhood of Lhassa. 
Not nearly so complete a series is that of Mount Sirban, but it is not the less 
interesting, because one of the most easterly localities for marine fossils, south of 
the first crystalline zone. Here lie, unconformably on the palaeozoic schi.sts, red sand¬ 
stones and thick silicious dolomites, whose position in the mosozoie succession of 
beds remains uncertain, as fossils are wanting. Above these come dark, thick- 
bedded limestones,with silicious concretions, and sections of Megalodon and Bicero- 
cardium. The limestones pass up into thin-bedded limestones and slates, which 
appear to be equivalent to Stoliezka’s Tagling limestone. The Sjoiti shales rest 
unconformably on these, a.nd are succeeded upwards by grey sandstones, the equi¬ 
valents of the Gienmal sandstone, and finally by hard, sandy limestones, with Gault 
fossils. Grey, thin-bedded liraestoneswithout fossils conclude the mcsozoic series. 
With similar development, but generally decreased thickness, and with the Spiti 
shales generally replaced by a few limestone beds, the mesozoic formations 
stretch away westward along the Chittapahar into the country of the Afridis. 
The mesozoic formations of the Salt Range are rather better developed 
Above the uppermost beds of the palseozoic come, firstly veiy hard,flaggy limestones. 
