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proves to be so rich in some of the rarer forms of insect life that I hope he will 
shortly redeem his promise of giving us a more extended paper on the entomolo- 
gical fauna of Woolhope, when he will no doubt point out to us how it happens 
that the varied geological formations, the alternation of hill and vale, and the 
diversified surface, favour the existence of species that are rare or wanting in the 
more level districts of the county where the Old Red prevails. 
In the various references to the geology of our primeval home which occur 
in our transactions, there is always more or less implied, sometimes very distinctly 
stated, a catastophic theory of its formation which I think must be even in excess 
of that at any time held by Sir Roderick Murchison himself, whose views 
especially favour that theory, no doubt, and any of whose opinions must meet 
with an almost superstitious respect throughout the Silurian kingdoms. Such an 
exaggerated form of the theory is no doubt due to the exigencies of our existence 
as a field club. Such accounts of the physical history of the Valley of Woolhope 
as we have, necessarily compress its events into a brief outline, and bring most 
clearly of all before the imagination the immense amount of dendation that has 
taken place. Speaking of the Woolhope Valley, Sir Roderick himself says, 
“What agency, I ask, except that of very powerful currents of water, could have 
removed every fragment of the debris that must have resulted, whether at one or 
several periods of elevation, from the destruction of all the superposed arches of 
' rock, and have scooped out all the detritus arising from such destruction, from 
the circling depressions, the central dome, flanking ridges, and former cover of 
those Silurian strata?’ So far all may agree ; at least if ice be included when 
water only is mentioned, and if periods of elevation be understood to be more or 
less long-continued periods, and not comparatively momentary epochs. But when 
she continues: ‘‘ And if that water had not been impelled with great force, caused 
by sudden uprises of these rocks from beneath the Old Red Sandstone, what other 
agency will account for so complete a denudation, the broken materials having 
only found issue by one lateral gorge, which was, we see, opened out by a great 
transverse fracture of the encircling ridges” (Siluria, p. 492—20th edition). 
Any attempt to form a clear idea of the hypothesis implied must convince 
us of its impossibility, I had almost said absurdity. There has been a great 
upheaval of the earth’s crust at the Woolhope Valley, and how rapidly it took 
place, we shall probably never know. But endeavour to imagine an upheaval so 
sudden and violent as is implied in the extract I have just quoted. Suppose the 
district to be submerged under any depth of water you think will produce the 
greatest effect, and it is very probable that since the Old Red epoch this district 
has lain under perhaps 2,000 feet of water. Your upheaval is by hypothesis at the 
site of the Woolhope Valley : now this will not produce violent currents at that 
place; the violent currents will be all around, radiating from the site of the 
upheaval as a centre; the denudation will be not of the valley itself but of the 
surrounding circle, a subsidence would bring a return current, and would pile up 
debris at the site where we wish to explain denudation. Any repetition of sudden 
upheavals and subsidences would bring us no further. 
