Page:Quarterly Journal of the Geological Society of London, vol. 28.djvu/509

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1872.]
DAWKINS—CLASSIFICATION OF PLEISTOCENE STRATA.
415

glacial or Pliocene on the one hand, and with the Late Pleistocene on the other, it will be seen that they are linked to the former by the Rhinoceros megarhinus, and to the latter by the Ovibos moschatus. The absence of the Reindeer, which was so numerous in the valley of the lower Thames, and the abundant remains of the Stag, seem to me to point backwards rather than forwards in time, and to imply that the Lower Brick-earths are not of Late Pleistocene age, just as the absence of the characteristic Early Pleistocene species shows that they are not of that age. The evidence seems to me sufficient to establish a stage intermediate between the two. Nevertheless the evidence is sufficiently conflicting to cause Dr. Falconer to come to the conclusion that these strata are of Pliocene date, and Mr. Prestwich to believe that they belong to a late stage in the Pleistocene[1].

The same group of animals, with the exception of the Megarhine and Tichorhine Rhinoceros and the Musk-sheep, is furnished by the fluviatile deposit at Clacton, in Essex, in association with the peculiar form of Fallow Deer which I have described under the name of Cervus Browni.

One of the most remarkable facts brought to light by Mr. McEnery is the former presence of the sabre-toothed Felis (Machærodus latidens) in the cave of Kent's Hole. Its characteristic canines are found associated with thousands of the teeth of Horse and Hyæna. Kent's Hole is the only place where this fell carnivore has been found along with the remains of Mammoth, Reindeer, and other Pleistocene mammals. It belongs to an archaic type, which sprang into existence during the Miocene times in France, Germany, and Switzerland, and preyed upon the Hipparion and Antelope in the plains of Marathon and on the Indian flanks of the Himalayas—to a type that coexisted with Elephas meridionalis and the Mastodon during Pliocene times in France, Germany, Britain, and Italy, and in South America preyed upon the gigantic Sloths and Horses whose remains are found in the Brazilian caves.

The large masses of breccia which occur in the cave-earth of Kent's Hole are remarkable for their hard crystalline structure, and prove that there was a stalagmite floor in the cave before the introduction, of the earth, and long before the formation of the present stalagmite pavement. In a portion of the cave called the "gallery" there is evidence of the undisturbed part of this ancient stalagmite in a "ceiling, or uppermost floor," that extends from wall to wall, "without further support than that furnished by its own cohesion. Above it there is in the limestone-rock a considerable alcove. This branch of the cavern, therefore, is divided into three stories, or flats,—that below the floor occupied with cave-earth, that between the floor and ceiling entirely unoccupied, and that above the ceiling also without a deposit of any kind." From its being stained with cave-earth, as well as from its position, the ceiling, at the time of its deposition, must have been supported by cave-earth. It would, indeed, be as impossible for a solid horizontal sheet of stalagmite to be formed in mid

  1. Falconer, Palæont. Mem.; Prestwjch, Geol. Mag.