224 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. .Jan. 6,
a great valley of elevation, the line of the volcanos being its anti-
clinal line.
Mr. Malcolmson and others have established the age of certain
beds connected with the eastern margin of the trap. Dr. Leith's dis-
covery bids fair to determine the age, on the western margin, of the
beds above the regular trap and below the basalt capping.
Professor Orlebar is of opinion that he has discovered a sort of in-
tercalary volcano, below this basalt, in Salsette.
I have collected a great number of specimens, and I hope, during
the next eight months, when I shall be under canvas, to add to them,
and so far to arrange them as to render them worth the acceptance of
the Society, when perhaps some competent geologist may be induced
to take the matter up.
4. On the Batracholites, indicative of a small species of Frog
(Rana pusilla, Ow.). Addendum to the Communication from G. T.
Clark, Esq., Bombay. By Professor Ow^en, F.G.S.
The portions of shale transmitted by Mr. Clark contain delicate, but
for the most part distinct, traces of the, generally, entire skeleton of
small anourous Batrachia ; the osseous substance is black, as if
charred.
The number of vertebrae, atlas and sacrum inclusive, is nine : the
caudal vertebrae are fused into a long, slender cylindrical style, as in
most anourous Batrachia.
Fig. 1. Fig. 2.
In the specimen (fig. 1) which lies on its back, the posterior
convexity of the vertebral bodies is shown.
The short, subcylindrical and very slightly expanded lateral or trans-
verse processes of the sacrum, and the absence of ribs or their rudi-
ments in the dorsal vertebrae, with the proportional expanse of the
skull and length of the hind-legs, show the specimens to belong to
the family of Frogs (Ranidce) .
There are seven abdominal vertebrae, with long and subequal trans-
verse processes, that of the second (third vertebra including the atlas)