Barry: Sylvan Vegetation of Fylingdales. 425, 
and that after the Elm and the Ash had been left behind in the 
upper part of the gills, it must have been almost without a 
competitor. 
In strange contrast, however, with the Oak’s ubiquity is the 
shyness of its fruiting. Such a thing as a regular acorn year, 
as one sees frequently in the Midlands and occasionally in the 
inland parts of Yorkshire, I have never witnessed here, and 
never expect to witness. Indeed, down to 1893, the sight of a 
ripe acorn was a very rare one, and Fylingdales acorns were 
indelibly associated with green fruit in their cups blown off by 
autumn gales. Since then, and since our cycle of dry summers, 
experiences in regard to acorns have been different ; but even 
in the best years it has been only on the outer and sunnier 
edges of the Oak woods, or on hedgerow Oaks in sheltered 
situations, that I have observed acorns in any quantity. 
Oaks and the Caterpillar Plague.—This scarcity of mast 
may possibly be connected, at least during the last twenty-five 
years, with the ravages of the caterpillar of the Oak leaf 
Roller: Moth (Zorérix viridana). On an average of perhaps 
three seasons out of four, during the period just mentioned 
(prior to that there was nothing of the kind), the Oak woods 
have been almost entirely stripped from this cause; the 
general appearance presented in the beginning of July being 
about the same as that in the beginning of May, ze., a few 
trees (mostly Elms) in leaf, and a few signs of green on the 
rest. By the end of July the foliage recovers, and the Oaks do 
not appear to suffer, as far as I can see, in general health 
I believe, however, though I have not properly proved it, that 
those most affected fail to bear fruit. 
Last year, and for the first time, at any rate to any great 
extent, the foliage of the Hazel undergrowth was likewise 
devoured. This, on the other hand, unlike that of the Oak, 
made no recovery during the rest of the year, nor has it done 
so this present season. The consequence is that great numbers 
of the Hazel bushes, and particularly the younger ones, are 
now in a dying condition, and in some cases dead. 
When the caterpillars are at their height there is a sound 
throughout the woods as of a light but continuous shower of 
rain. This is, of course, from the fall of the excrement. At 
the same time the insects themselves are noticeable, from their 
habit of letting themselves up and down by long silken threads. 
In making your way, therefore, through the coverts, you can 
scarcely avoid coming in contact with them, as they hang about 
1907 December is 
25 
