320 Reviews— The Geology of India. 
Introduction.—Mr. Holland remarks that, in attempting to express. 
these two distinct geological stories in European terminology, we find’ 
that our simplest and most easily translated characters are preserved 
in the marine fossiliferous strata, while it is practically impossible to 
correlate directly the land and fresh-water formations which are so 
largely developed on the Peninsula with their equivalent stages in the 
European standard scale. He also specially points out, by way of- 
illustration, that the flora ‘“‘ which flourished in the great river valleys 
of the old Gondwana continent did not make its appearance in Europe 
until well on in the Mesozoic era, yet, from other evidence, we know 
that the lowest Coal-measures in India were being formed during 
Upper Paleozoic times.”” He further insists upon want of strict 
contemporaneity in geological formation, and strongly advocates the 
use of local stratigraphical names. 
In the classification of Indian strata there is a trace of a datum-line 
in the WVeobolus-beds of the Salt Range, which may be regarded as the 
equivalents of the Olenedlas-zone in other Cambrian areas. 
To the ages preceding the date at which the LWeobolus-beds were 
formed he refers— 
(a) The great mass of crystalline schists which are exposed over 
half the Peninsula, forming the old floor on which the unaltered 
sediments were laid down. 
(6) The great thicknesses of unfossiliferous strata known by such. 
local names as Gwaliors, Cuddapahs, and Vindhyans. 
The ages following the Lower Cambrian Period have left their 
record in two groups— 
(c) During the Paleeozoic era deposits were formed in the extra- 
peninsular area with fossil remains referable to one or other of the 
well-known systems of Europe from the Cambrian to the Car- 
boniferous. No records of this era have been preserved in the 
Peninsula. 
(d@) From Permo-Carboniferous times to the present day we have 
a double history: a record of life and events on the stable Peninsula, 
and a series of deposits formed in the adjoining ocean, whose bed: 
was afterwards upheaved to constitute the extra-peninsular parts of 
India. 
Thus Indian rocks fall naturally into fow great groups: two below 
the Olenelius datum-line without fossils, and fwo above the horizon 
at which the oldest recognizable fossils occur. These four groups are 
distinguished in the order of priority as (1) the Archeean, (2) Purana, | 
(3) Dravidian, and (4) Aryan groups. . 
The Pre-Cambrian History of India may be said to contain three 
elements, viz., the Archean era, the great Eparchean break, and the 
Purana era. 
The Archean rocks, which occupy so great an extent of peninsular 
India, are sometimes spoken of as the ‘fundamental complex.’ 
This essentially agrees with its development in other countries, and 
notably in America. ‘‘Some of the rocks forming this complex are 
masses of deep-seated igneous origin: others presumably originated 
as sandstones, shales, limestones, lava-flows, and other forms of 
superficial deposit, which became metamorphosed by close-folding, by - 
