CAVES AND CAVE DEPOSITS, 177 
banked up on the upper side of the hedge, so that there is a fall 
of some eight feet from the field on the upper side of the hedge 
to the natural level below it, which also has been somewhat 
lowered by the general working of the soil down the slope. 
This superficial talus is the upper part of what has been dug 
through at the upper or swallow-hole entrance of the cave, yet 
it has not been distinguished as different from that which has 
by some been taken as part of the main mass of the drift. If, 
after an inspection of the ground, any doubt remained as to the 
recent date of some, at any rate, of the material which covered 
the northern mouth of the cave, and which was all equally 
referred to the age of the Clwydian drift, a more careful inspec- 
tion of the glaciated stones out of the mass should dispel it. 
There were plenty of glaciated stones, as mav be found every- 
where along the flank of the hill; but some of these, in addition 
to the more or less well-preserved glacial striz, carried the rough 
irregular grooves of agricultural implements. The tilled soil 
and the rainwash rapidly accumulates on ledges. and against 
fences on the slopes of the Clwydian range. 
I do not for a moment deny the possibility, or even proba- 
bility, of our some day finding a cave which was formed before 
the great Clwydian-drift submergence, or even before the great 
Snowdonian ice rode over the Vale of Clwyd on to the Cheshire 
plains ; but such caves will be few, and theirage hard to prove, 
for many will have been altogether destroyed by denudation, 
and most will have got swilled out by marine and subaérial 
currents, and no trace of their first inhabitants will have been 
left. The question is one of so great interest that we are justi- 
fied in asking for very clear evidence in each case in which it 
is stated that remains of such antiquity have been found in 
caves before we admit the proof. Turning now from the strati- 
graphical to the palzontological evidence, we get the same 
result. If ever we come upon pre-glacial caves we may expect 
Pliocene animals, and if we find caves belonging to an age 
anterior ta the great submergence, it is probable that the animals 
whose remains are found in them will belong to an older group 
than those found in deposits later than the submergence. But 
we have not an older group in the Ffynon Beuno cave. We 
find there the animals of the newer post-glacial gravels of the 
South and East of England. The absence of shells in any of 
these deposits, as far as such negative evidence is of any value, 
certainly goes to confirm the idea that they have been much 
modified, if not transported down-hill by subaérial action. 
Fragments of shells are found not uncommonly in the Clwydian 
drift, along the River Elwy, but not in the deposits which most 
resemble it about Ffynon Beuno. [They have since been found, 
see below.] Moreover, the surface of the limestone fragments 
was decomposed in the drift outside the cave, leaving the less 
soluble bands sticking out in sharp relief, and showing a 
chemically-fretted surface, and not such as is seen on stones 
rolled in acurrent, though common on those found travelling 
