322 Reviews —The Geology of India. 
geological history of the Salt Range is a blank between the lowest 
Cambrian and the Permo-Carboniferous, but there are indications 
here and there of the older Paleeozoics in the central Himalayas, 
where the Vaikritas and the Haimantas are regarded as Upper 
Cambrian. The Ordovician is represented in the Kumaun area by 
a coral limestone; while in Spiti this stage is probably not preserved, 
the lowest of the Silurian beds being red grits and quartzites, with 
overlying shales and limestones, which contain fossils like Halysites 
catenularva, indicating an Upper Silurian (Gothlandian) age. The 
Gothlandian beds are overlain by a grey-to-red limestone, which has 
not yielded fossils sufficiently well-preserved to determine its exact 
age, though from its position it is probably Devonian (Muth Beds). 
A Devonian fauna has been proved to exist in Chitral, the evidence 
being based chiefly on unusually well-preserved Brachiopods, though 
with a mixture of Corals approximating to Upper Silurian forms, and 
Devonians have also been recognized in Upper Burma. 
Above the Muth quartzite there occur grey limestones with 
numerous Brachiopoda of Upper Carboniferous age, together with 
associated deposits containing Phillipsia, Fenestella, etc., probably of 
Upper Carboniferous or Permo-Carboniferous age. With these beds, 
the author says, we approach the close of the Dravidian era in 
Northern India; for at about this horizon, corresponding to the 
Upper Carboniferous of England, there is an important break in the 
deposition, and new conditions are introduced by a widespread con- 
glomerate which forms the base of the marine sediments distinguished 
as the Aryan group. 
B. The Aryan Era. 
This is the most extensive and important of the four primary 
divisions adopted by Mr. Holland, being equally well represented 
by marine formations in the extra-peninsular areas as by fresh-water 
and terrestrial formations in the peninsular area. Its description 
occupies three-fifths of Mr. Holland’s article, and, as it is not possible 
on the present occasion to go into particulars, we append the table of 
the Aryan group as set out on p. 55, once more reminding the reader 
that the Aryan group represents everything from and including the 
Permo-Carboniferous up to the present day. 
In the extra-peninsular area the changes in physical geography 
which occurred towards the close of the end of the Carboniferous 
period are marked by a widespread conglomerate in Spiti and 
Kumaun. This conglomerate forms the basement bed of a great series 
of strata which were laid down successively, without a sign of 
interruption or break, throughout a period corresponding to the whole 
of the Permian and the succeeding Mesozoic era of Europe. This 
same boulder-bed, of course, looms largely in the Salt Range, where 
ice conditions have been claimed for its origin as well as for the 
analogous Talcher boulder-bed of the Gondwana system. Above this 
are various beds, some of which contain a prodigious wealth of Permo- 
Carboniferous marine fossils. We cannot afford to discuss these, but 
a few words on the Gondwanas of the Peninsula may not be out 
of place, since, from an economic point of view, this is the most 
important of all the Indian formations, and possesses a further interest 
