88 REPORT—1857. 
south of east and north of west. The section in ascending order of the basin shows 
at the base sandstone and blue shale, but slightly fossiliferous in thickness from 500 
to 600 feet; over these is a series of shales and sandstones often micaceous, occasional 
beds of ironstone, and thin layers of coal and coally shale, giving a total thickness of 
about 1800 feet; and over these again is a distinct series of quartzose grits, congio- 
merates, and sandstones, in thickness from 1600 to 2000 feet. These three groups 
are unconformable each to the other ; the unconformity between the two lower being, 
however, much less marked than that between the two upper. To tne lower group, 
as having been first recognized and described in this district, the name of “ Talcheer ” 
series has been given; the second group, which, from its imbedded vegetable remains, 
was proved to be identical with the rocks of the extensive Damoodah coal-field when 
these were first described, has been denoted the “‘ Damoodah” series; while the upper 
group, supposed to represent the great series of rocks, so magnificently seen in the 
Mahadeva Hills of Central India, has been called the ‘‘ Mahadeva” series. Thus 
these series can be recognized in each of the extensive fields referred to, although with 
varying developments and thicknesses. At the base of the Talcheer series there is a 
remarkable bed, consisting of very large and only slightly rounded masses of granite 
and gneiss, imbedded in a fine silt, and occurring under such conditions as induce the 
opinicn that the action of ground ice has been the cause of its formation. In the 
Rajmahal district, there is a very limited development of the lower beds, above which 
unconformably comes the Damoodah series, here exhibiting a greater extension up- 
ward than in Cuttack; but unfortunately the sequence of the rocks is interrupted by 
the intercalation of several successive floes of basaltic trap, the intervals between 
which have been marked by the continued and tranquil deposition of the mechanical 
rocks going on. These floes have been repeated six or seven times, and the pheno- 
mena of contact are in all cases marked; the upper layers of the mechanical deposits 
in contact with the trap being in all cases greatly altered, while the lower layers are 
in no cases changed, but rest unaltered on the degraded surface of the underlying - 
trap. But while the actual physical sequence of the deposits cannot be here traced, 
the fact of their all belonging to the same great series is attested by the occurrence of 
some identical fossils throughout. A few species pass upwards through the series, 
but there is a very marked change in the general facies of the flora in the upper as 
compared with the lower portion of the group; the latter characterized by the abun- 
dance of Pecopteris, &c., the former by the abundance of zamia-like plants. The 
series, therefore, has been divided into Upper and Lower Damoodah rocks. For 
the details of the structure of the district, reference was made tothe maps. In the 
Nerbudda district the series was less interrupted, and there also the same general 
results were obtained. The southern boundary of this great field was for a large 
part of its course produced by a great fault, having, guam proxime, the same general 
direction as that of the faults bounding the Talcheer field. The age, geologically 
considered, of these Damoodah rocks was briefly referred to. A large series of draw- 
ings of the fossil plants from them were exhibited, and the fact of the general oolitie 
facies of this group, especially of those from the upper beds, peinted out. The 
difficulty of the question was alluded to, especially in connexion with the disco- 
very, on the one side, of several species identical with those found in these Indian 
rocks in the Australian coal-fields, associated with numerous animal remains distinetly 
referable to the lower carboniferous era; and, on the other hand, with the discovery 
in Cutch of other species, also identical with some of these Indian forms, in beds 
associated with animal remains, undoubtedly referable to the ooliticepoch. It must, 
however, be borne in mind that the latter forms, or those which the evidence of asso- 
ciated animal remains would show to be oolitic, are only found in the upper beds of 
the Damoodah series, while those which are common to the Australian fields are those 
chiefly found in the lower beds. Unfortunately, no animal remains whatever have 
been found with these plants in the districts examined, excepting some annelide tracts 
useless as distinctive forms. He preferred, under these circumstances, waiting for 
further evidence before giving any definite opinion as to the age of this widely-ex- 
tended and important group of rocks. Mr. Oldham then stated that there seemed 
good reason for separating altogether from the several groups of rocks to which he 
had referred the whole of the great thickness of sandstones which formed the great 
Vindhyan range, extending almost entirely across India, from the mouths of the 
