EASTERN BRITISH PLIOCENES.
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Chalk and chalk-flints are the most abundant of the rocks,
often covered with Balani and mostly unworn, showing very few
traces of travel. Prestwich suggests that the heavy porphyritic
block he found at the base of the Coralline Crag at Sutton was
brought in by ice, but so far there is nothing to prove that it
was not deposited on the London Clay it was found upon, long
before the Crag sea came into existence, as it may be the other
stones did also, there being every reason to believe that a land
surface had existed in this part of N.W. Europe from Mid-
Eocene times.
Many of the flints are scratched, but it is not safe I think
to refer every scratch to ice agency, as is too often done. The
porosity and texture of flints and the molecular changes they
may undergo is too little known to dogmatise upon.
Attention has been directed to these flints, and the land
surface they lie upon, by the discoveries of Mr. J. Reid Moir,
of Ipswich, who has found a number of chipped flints, in associa-
tion with box stones, rolled bones deeply phosphatised, coprolites
and unworn flints, which rest upon the London Clay, beneath
true and undisturbed Crag in and about Ipswich. These flints are
often massive, flaked as for a definite purpose, and utterly
unlike anything that has yet been obtained from the later
deposits, nor have they any relation to the Eoliths so plentiful in
nearly every gravel deposit about the district. The suggestion
that they are of human origin requires further evidence. I
should refer them to some flint-chipping precursor of the
genus Homo, such as Pithecanthropus, or something of the
Homo heidelbergensis type, both of them being now classed
by some writers as later Pliocene or equal to our Forest Bed,
with which the fauna associated with the Heidelberg (or
Mauer) jaw, is said to have many affinities like Rhinoceros
etruscus, etc. A jawbone found on a heap of Coprolite in a
pit at Foxhall, near Ipswich (1866 or 67), is just now much in
evidence. Undoubtedly old, there is no evidence to associate
it with the chipped pre-Crag flints, and this bone is now unfor-
tunately lost. For other supposed evidences of man in the
Crag period, I may refer to an early paper of mine in the
Geological Magazine, 1886 ("The Succession of the later
Tertiaries in Great Britain"). Had it been a genuine Red Crag
fossil, it is hardly likely that the diggers, who had a keen eye