124 PROCEEDINGS OF THE GEOLOGICAL SOCIETY.
tion; but under what circumstances this could have taken place, and
whether before or subsequently to the deposition of the laterite in
the low country of Goozerat, does not seem to have been inquired
into. The inquiry may be recommended to Indian geologists as
one of great interest.
P.S. — Since writing the foregoing remarks on the probability of the Indus or some large river from the north having once found its way into the Gulf of Cambay, I have seen quotations from Prof. Max Muller's translation of the Vedas, which prove that at the time some of them were composed, the Suruswuttee, the most easterly of the Punjaub rivers, which now loses itself in the desert of Rajpootana, flowed into the Indian Ocean. This confirms to some extent the theory of the cause of the alluvial deposit at the head of the Gulf of Cambay.
3. On the Rodentia of the Somerset Caves. By W. A. Sanford, Esq., F.G.S.
(Read June 23, 1869*.)
[Plate VIII.]
Having recently examined the collection of Rodentia from the Somerset Caves in the Taunton Museum, I find that several of the specimens cannot be referred to species which have hitherto been considered members of the fauna cotemporary with the Mammoth (Elephas primigenius) in Britain.
1. Genus Arvicola. — As usual, bones and teeth of one or the other of the closely allied species, or perhaps varieties, which are about the size of, and have a dentition similar to that of Arvicola amphibius, abound in the Somerset Caves; but they are all fragmentary, and, as the observed differences between these species principally depend on the proportions of different parts of the animals, and not upon differences of form of the parts themselves, it is useless with our present materials to attempt to determine to which of these forms the fossils belong; it will be convenient to class them, as hitherto, as the bones of our common Water-rat (Arvicola amphibius, Linn.).
2. Arvicola glareolus (Schreber)=pratensis (Baillon)=riparia (Yarrell), appears to be a rare cave animal. We have never met with but two jaws; one of them is from Hutton Cave, and is in the Taunton Museum.
3. We have met with several lower jaws the dentition of which is identical with that of Arvicola agrestis (Linn.); but the diastema between the molars and incisor is longer, and the lower jaw itself is straighter in this part than in the recent jaws with which we have compared it. In this the jaws approach Arvicola ratticeps (Blasius); but we do not regard the difference as other than varietal.
4. Among the bones hitherto referred to Arvicola agrestis we
- See p. 444 of the last volume.
