98 PROFESSOR T. MCKENNY HUGHES, M.A. 
‘ 
had, and especially so as placing the drifts of Wales more closely in relation 
with those so widely distributed in Canada, than heretofore. In the present 
paper he has very clearly illustrated, in the case of Ingleborough Cave, the 
fact that true uniformitarianism in geology includes local and occasional 
catastrophic action. This I regard as of the most vital importance to 
geological reasoning, and especially in the explanation of cavern deposits 
and river gravels, which, more than most other formations, are liable to be 
affected by violent and paroxysmal local dehacles, as well as by appar- 
ently capricious accidental changes. The utmost caution and the most 
careful and minute observation are necessary in dealing with these 
deposits, and in estimating their ages and their relation to the human 
period. 
“With kind regards, 
“*T remain, yours truly, 
“J. Witttam Dawson.” 
“ Captain Francis Petrie.” 
The Rev. J. Magens Mello, M.A., F.G.S., writes :— 
“T am very sorry that I am unable to be present at the reading 
of Professor McKenny Hughes’s paper this evening. To the greater 
part of it I have nothing that I could add save in the way of corro- 
boration from personal observations of similar instances. But I have 
the very strongest doubts whether there can be any trace whatever left 
in our caves of the Noachian Deluge, even granting that catastrophe 
involved our islands, whieh I am hardly prepared to admit. My own 
experience of British caves, both from observation and from reading, tends 
to show that the contents of at any rate, most of them have been the ‘gradual 
accumulation of a long series of years, during which they were oceupied 
partly by beasts, partly by men, and that there is no evidence whatever to 
be found in them of so sudden a cataclysm as the Great Flood, the historical 
character of which is, however, abundantly confirmed by overwhelming 
: ? ? 5 
proofs of various kinds.” 
The Rev. Dr. Walker, F.L.S., says :— 
“Dun Mallard, Cricklewood, 
“ February 19. 
“On p. 96, Professor McKenny Hughes speaks of the appearance of ‘the 
wingless, colourless grasshopper in the mammoth cave.’ I should be glad 
to be informed whether or not the same species, winged and coloured, 
is found outside the caves in broad daylight ? If not, the infer- 
ence would seem to be that the grasshopper in question had originally 
been created sightless, to fit it for its natural surroundings, and not have 
gradually become so through the unused organ being atrophied and lost. 
As it is inconceivable that any particular species would survive in the dark 
cave, and have disappeared long years since in the open air, where all the 
conditions for supporting and prolonging existence are so much more favour- 
able. Lastly, short antennse and the possession of wings are not the 
characteristics of all grasshoppers living in the light, as I can prove by 
Species captured by myself and in my own collection.” 
