26 
But these instances do not help my point further than they go to- 
show that practically all larvas are protected in some way or another, 
and in those species of larvae which are in no way protected in colour 
or shape to their surroundings, many of them conceal themselves from 
view, and others appear to be unpalatable to their enemies owing to 
the hairs which they carry. Hence the whole of the lepidopterous 
larvae are protected. Then why should P. betularia and G. bidentata 
possess any special attributes of inheritance which the rest of the 
lepidopterous larvie do not possess, and yet without those special 
advantages they are able to hold their own. 
My conclusion must be that the similarity of larvae to their 
surroundings has come about by a direct response in the nervous 
system of the insect to assimilate to its surroundings, whether in 
colour or form, and in most cases I should expect that it has come 
about very rapidly. 
Natural selection as a theory is very fascinating, but when we see 
larvae like P. betularia, Gonad ontu bidentata, aud others, assuming a 
totally different aspect in one season to suit their environment, it is 
obvious that these changes have not arisen from an accidental variety 
with the influence of inheritance to bring about the result. Further¬ 
more, I have a strong feeling that the rapid growth of the melanie 
forms of lepidopterous insects in the imago state, in certain districts, 
has been too great for the action of the natural selection to have 
produced the result in so short a time. This of course is only a 
matter of opinion, as anything like definite evidence is difficult to get; 
but in watching Taeniocampa opiiua in my own district it has appeared 
to me that during a few years, when the ground on which they are 
found had been repeatedly burnt, that specimens taken during that 
time were decidedly darker, to correspond with the ground on which 
they rested. I believe that it was in 1881 that I first saw T. ojdiua 
from here, and then all that I saw were grey, not very unlike the usual 
Cheshire specimens. I did not see the insect again until 1892, when 
they were nearly all decidedly darker, and since that time they have 
been as nearly black as could be, particularly during the time when 
the ground was most burnt, and last year and the year before they 
were undoubtedly somewhat lighter again, as both these seasons have 
been too moist to have any great amount of burning. This of course 
is only circumstantial evidence, but to my mind it is strong. And. if 
my observations are correct, it appears that the changes have been too 
rapid to be produced by natural selection, as its action must of necessity 
be very slow. Before dismissing the subject we might revert to the 
protective methods of Phoroiiexma swaragdaria and P. bajularia, which 
I have already mentioned as covering themselves with their food plant. 
This supplies all that natural selection is believed to fulfil, but how are 
we to attribute it to that cause? I confess I am at a loss to see. 
Although it is always conceded that to admit the existence of one 
mystery in nature will not prove the existence of another, yet I cannot 
help thinking that as the nature of the influence of heredity is surely 
past human conception, seeing how in one germ it is possible to 
transmit disease, physical power, appearance, mental capacity, or 
otherwise, it is not too much to believe that a beneficient nature 
produces varieties favourable £o their continuance, rather than to 
believe that the whole fabric of nature has been built up on accidental 
