72
THE ESSEX NATURALIST.
shown to be derived from an earlier gravel as some of the abrasion
chips are later than the major patination.
No. 90a is a rude Chellean scraper in marbled flint.
No. 35c is a flake, trimmed to a point by flaking along two
sides meeting at an angle : a precursor of the Mousterian ''point.''
Nos. 85c and 131. These are two interesting finishing
flakes, scaled off the surface of implements in the last stages of
manufacture, and carrying on their outer surfaces the facets
of the earlier stages of the flaking process. No. 85c shows a
fragment of the edge of the implement carried away at the butt-
end of the finishing flake. Various points in the methods of this
technique are further explained in the Journ. Roy. Anthrop. Inst.,
vol. xliv., 1914, p. 423 ("incurved flaking") ib., vol. xlix., 1919,
p. 358 ("thinning flakes").
Leyton.
No. 12 (Plate IX., fig. 5) is a rather large, broad-pointed
implement, unabraded and with untrimmed butt, size 146 x 79 x
41 mm. It appears to be made from a Chalky Boulder Clay flint.
No. 34d. This is a fragment of what was originally a very
fine example of the "oldest class" of Worthington Smith, It
was apparently a flat ovate, deeply ochreous, much abraded,
and derivative from an older gravel.
No. 115b (Plate IX., fig. 3) is a smaller but very characteristic
example of the same "oldest class" as No. 36c (Plate IX., fig. 1) ;
it chances to have a natural perforation. Size 84 x 53 x 22 mm.
No. 79 is a rude discoidal form.
No. 32c is a thick, clumsy, sub-ovate implement.
Various rude pointed implements are Nos. 5a, 366, 89c, 90c
98, and 100e.
The above are, in all probability, from the 50-foot, Middle,
or Taplow, Terrace, as it is variously called.
Plaistow.
The implements in the collection registered from this locality
are evidently from a somewhat late gravel (as one would expect
from the locality) containing the sweepings from older gravels of
varied date. Four, namely, Nos. 1c, 30a, 93, and 113a, are
much rolled and damaged derivatives of Lower Palaeolithic
form.
No. 56a is a heavy rude flake, ochreous and sub-abraded,