4 
RecofcU of the Geological Survey of India. 
[voL. XIII. 
felspar and a dark.green mineral principally, if not all, biotite, and it seems, in¬ 
deed, to be the core of a volcanic focus. Tbe annular ridge surrounding Girnar, 
outside a deep intervening valley, is largely made up of tracbytic dykes and 
bedded basaltic masses -vvitb a quaquaversal slope. 
In Rajputana Mr. Racket added a very large area (more than 10,000 square 
Bajputaiia: miles) to his previous survey of the Arvali region, ex- 
Mr. Eaol-ei. tending to the south-west as far as Erinpura. The scat¬ 
tered position of the outcrops in a wide-spread waste of sand makes such a result 
possible. As soon as the area to the east of the range is filled in, up to the Vin- 
dhyan scarp near Biindi, as Mr. Racket hopes to accomplish during the present 
field season, a connected account of this portion of the region, up to Delhi, can 
be published. 
The Vindhyan strata were found to cover a large area to north and east of 
Jodhpur. Their most north-easterly outcrop is at Khatu, 80 miles north-by. 
east from Sojat. They everywhere rest flatly upon the old rooks—the gneiss, the 
Raiiilo schists, the Malani felsites, or the Alwar quartzites. There is generally a 
thin band of fine quartz conglomerate, or of green shales, quite unaltered, at the 
base, overlaid by pale fine sandstone like the Kaimur rock, to which succeeds 
a red r’ock like the Bhanrer sandstone. The whole varies in thickness from 
100 feet at Sojat to 350 feet at KbMu. There is sometimes a conglomerate 
between the two types of sandstone. Cherty calcareous beds are associated with the 
red sandstone at top, thus connecting this rock with an overlying limestone that 
covers large ar-eas; it is locally 200 feet in thickness. 
A very peculiar boulder formation is described as occurring on and about the 
Vindhyans, especially the limestone, yet not belonging to them. The blocks, up 
to 3 feet in diameter, are thoroughly water-worn, formed exclusively, so far as 
observed, of the Alwar quartzites. They lie loosely, without any matrix, in banks 
sometimes more than 100 feet thick. 
The felsitic eruptive I'ocks described by Mr. Blanford as the Malani beds, 
south of Jodhpur, are considered by Mr. Racket to belong to the Raialo horizon, 
as he found typical beds of that rock associated with the schists north of Dewair, 
in the centre of the Arvali range. 
In the Extra-Peninsular area there were two survey parties at work in the 
cold season of 1878-79 ; and in the summer of 1879 two were engaged in the 
high Rimalayas. 
With the new maps of KumaunMr. Theobald surveyed, or at least explored, 
Sub-Himalaya : the belt of tertiary rocks at the base of the mountains be- 
Mr. Theobald. tween the Ganges and the Kali, in continuation of the 
work done sevei'al years previously to the west of the Ganges. Since these lower 
hills have been so extensively taken up for forest reserves they have become more 
inaccessible than ever, the temporary villages and the paths connected with them 
having disappeared. 
The Siwaliks of this region (if indeed the strata of these flanking ridges 
include true Siwaliks, as Mr. Theobald seems to think) still maintain their 
character as unfossiliferous, no success having rewarded the search of so 
