"‘■'••^UaxidaDevi 
25 6 6o. 
[VOI;. XIII. 
8‘i 
Records of ike Geological Survey (f India. 
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S 5 
S 5 
TIlo features may roughly be sketched 
as shown in the annexed section, in 
which I have, of course, omitted all the 
numerous minor folds and a few faults 
and dislocations which must of necessity 
occur whore such enormous tension ex¬ 
isted, 
2. Pre-Silurian rocis of the Himalayas. 
—Nearly all sections through the Hima¬ 
layas reveal on the northern slope and 
below the fossiliferous Silurian series a 
formation which has often been noticed 
and always been described as the “ Slate 
scries.” The lowest member of it is 
probably a gi’eenish silky and semi-meta- 
morphic slate, seen near Milam to pass 
into the schists below. But higher u]) it 
passes soon into a purple or dark blue 
quartzite in thick beds associated with 
beds of a peculiar jasper-like conglome¬ 
rate, which in some sections forms the 
lowest bed near the contact with the 
metamorphics. Not a single trace of 
fossils has been found in this group, 
which is very much contorted. It is 
now crumpled up into a narrow strip, so 
that its thickness cannot even be guessed 
at. 
Higher beds, consisting of silky green¬ 
ish slates, quartzites, and lastly, of a 
dense rod quaitz-slate, seem at a few 
places to rest unconformably on the lower 
group, and everywhere dip below the 
fossiliferous Lower Siluriuih formation. 
A few indistinct traces of Bii-alves, 
and Pleurotomaria ? Bollerophon ? were 
found in it. There is very little doubt 
as to the propriety of classing these last 
rocks with the Cambrian series of else¬ 
where, on the grounds of their relation 
to tho overlying strata, which by their 
fossil contents are abundantly proved to 
belong to the Lower Silurian system. 
The lower groiq) of quartzites and con¬ 
glomerates may then bo termed Lower 
Cambrians ; and the whole ro.sts more or 
