296 
BED OF FOSSIL SHELLS 
acids. Some of the small shells are completely changed 
into calcedony. Specimens of these shells are lodged with 
the Asiatic Society. 
It is a remarkable fact, that the only remains of animals 
hitherto discovered in India, should be found in trap-rocks, 
and under such peculiar circumstances. Imo, They are 
found in situations where there are no indications of the 
former existence of lakes; ^do, Both the shells and matrix 
are destitute of carbonic acid; Stio, The former are in 
many instances squeezed flat, without fracture, and in some 
cases commixed with their matrix. 
These effects could only have been produced by the 
agency of heat, and consequently the modern theory of 
submarine or subaqueous volcanoes will best serve to ex- 
plain the phenomena. These shells were deposited in the 
stratum of clay in which they are now found, and when 
forced up by the mass of wacke beneath, they were most 
probably at the same time covered by the nodular basalt. 
Thus we have heat to drive off the carbonic acid, and 
soften these shells, under a pressure which assisted the pro- 
cess, and at the same time flattened them. 
I have numerous collateral proofs of the intrusion of the 
trap-rocks, in this district, amongst the gneiss, which do 
not allow me to doubt of their volcanic origin. I shall take 
an early opportunity of completing the history of the trap- 
rocks of India, for which I have been collecting materials 
for several years past. 
Hyderabad, ) 
