Page:Quarterly Journal of the Geological Society of London, vol. 28.djvu/566

470 numerous portions of detached plates, in all probability belonging to this tooth, occur in the collection, I conclude that the specimen represents the last upper molar in a state of germ or nearly so.

4. The third specimen is a nearly perfect upper molar, entirely in the germ-state. It is about 3″ long by 2″⋅2 wide, and exhibits eight plates, and apparently had at least one or two more at the anterior end. It would therefore appear to be an m.m 4, or m 1, although, if so, it is of rather unusual width.

Mr. complimented Col. Lane Pox on the exactness and completeness of his description of the classical district which he had investigated, in which mammalian bones had been found and described by Mr.Trimmer so early as 1815. In that case Hippopotamus- remains, very fresh and unworn, had also been discovered. Prof. Morris had also described a deposit near Brentford in which numerous remains of Reindeer were present, showing how variable was the distribution of mammalian remains even in a limited area, and how unsafe it was to base theories upon merely negative evidence. It was to be hoped that other investigators would extend similar discoveries to other parts of the valley of the Thames.

Mr. did not think that the presence of the young Hippopotamus was absolutely conclusive of its having been born in this country. With regard to the presence of remains of Reindeer and Hippopotamus in the same beds, not only might there have been an overlapping of faunas such as has been pointed out by Sir Charles Lyell, but there might also be an intermingling of the included remains from two beds of different ages. He was not altogether satisfied with the evidence as to the coexistence of man with Elephas primigenius, nor as to the artificial character of some of the presumed implements. He did not attach any great importance to the merely fragmentary bones.

Mr. maintained that the implements exhibited were of necessity artificial, and commented on the nature of the evidence as to the coexistence of man with the Pleistocene fauna. Under any circumstances the gravels containing the implements could only have been deposited at a time when the Thames valley had not been excavated to any thing like its present depth; and they were therefore of great antiquity. There was, moreover, a notable absence in them of a number of the animals usually found associated with Neolithic implements; and if man had not subsisted on the animals the remains of which were found associated with his handiworks in the gravels, it was a question on what food he had had to depend. The absence of implements in the low-level gravels seemed to him significant of a diminution in the number of the human beings who frequented the banks of the river.