ARCTIC FAUNA AND FLORA AT PONDERS END. 37
find that they are of the stunted or dwarfed forms occurring
only under Alpine-Arctic conditions.
The determination of the mosses has been undertaken by
Mr. H. N. Dixon, and he has succeeded in naming 40 or more
species. The nearest assemblage to these would be found to-day
in Northern Lapland. Several of these, namely Tortula aciphylla,
Timmia norvegica, Hypnum fastigiatum, H. molle and H.
turgescens, are now either extinct in Britain, or are confined to
the summits of one or two of the highest mountains of Scotland.
Full reports on the fauna and flora are being prepared, and will
be presented to the Geological Society of London.1
The twigs and leaves of the dwarf Arctic willow occur in the
greatest profusion in the deposit, but no trace of the wood
of any larger tree has yet been found. The climatic conditions
represented must have greatly resembled the bleak tundra of
Northern Europe.
No such complete or definite evidence of this late Pleistocene
Arctic stage has previously been discovered in the South of
England.
LIST OF FOSSILS.
An asterisk is placed against the most abundant species.
The Mammalia were chiefly determined by Mr. E. T. Newton,
F.R.S.; the Mollusca by Messrs. A. S. Kennard, F.G.S., and
B. B. Woodward, F.G.S.; the Coleoptera by Mr. C. O. Water-
house, I.S.O.; the Entomostraca, etc., by Mr. D. J. Scourfield,
F.R.M.S., and Dr. T. Scott; the Flowering Plants by Dr. F. J.
Lewis, M.Sc., F.Z.S., and the Mosses by Mr. H. N. Dixon,
M.A., F.L.S. To all these gentlemen my best thanks are due
for their kind work.
Mammalia.
* Elephas primigenius. Bos (or Bison).
*Rhinoceros antiquitatis. Rangifer tarandus. (?)
*Equus caballus. Sorex kennardi.2
Dicrostonyx henseli
Mollusca.
Arion sp. *Sphyradium columella G. V. Mts.
Limax arborum Bouch-Chant. Vertigo parcedentata A. Brann.
Agriolimax lavis Mull. * Jaminia musccorum Linn.
1 See also "Arctic Plants from the Valley Gravels of the River Lea," Nature, vol. 85, p. 206
(December 15th 1910), and "Excursion to Ponders End and Chingford," Proc. Geol. Assoc.
vol. xxii., 1911, p. 166.
2 Martin A. C Hinton, Geological Magazine, dec. v., vol. viii., 1911, p. 533.