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APPENDIX E 
of observation, and, in addition, a man possessing the ability to 
portray vividly, clearly, and with interest what he has seen. 
Experience in the field is of great value in helping to test various 
biological theories. One of the theories which has had a very 
great vogue of recent years is that of the protective coloration of 
animals. It has been worked out with a special elaborateness in 
Mr. Thayer’s book on “ Concealing Coloration in the Animal 
Kingdom.” I do not question the fact that there are in all 
probability multitudes of cases in which the coloration of an 
animal is of protective value in concealing it from its prey or its 
foes. But the theory is certainly pushed to preposterous extremes; 
its ultra-adherents taking up a position like that of some of the 
earlier champions of the glacial theory, who, having really dis¬ 
covered notable proofs of glacial action in parts of Europe and 
North America, then went slightly crazy on their favourite subject, 
and proceeded to find proofs of glacial action over the entire world 
surface, including, for instance, the Amazon Valley. As regards 
many of the big game animals, at any rate, which are claimed by 
the ultra-exponents of the protective coloration theory as offering 
examples thereof, there is not the least particle of justification for 
the claim. 
I select Mr. Thayer’s book because it is a really noteworthy 
book, written and illustrated by men of great ability, and because 
it contains much that is of genuine scientific value. 1 I have no 
question whatever, for instance, that concealing coloration is of 
real value in the struggle for existence to certain mammals and 
certain birds, not to mention invertebrates. The night hawk, 
certain partridges and grouse, and numerous other birds which 
seek to escape observation by squatting motionless, do unquestion¬ 
ably owe an immense amount to the way in which their colours 
harmonize with the surrounding colours, thus enabling them to lie 
undetected while they keep still, and probably even protecting 
them somewhat if they try to skulk off. In these cases, where the 
theory really applies, the creature benefited by the coloration 
secures the benefit by acting in a way which enables the coloration 
to further its concealment. A night hawk, or a woodcock, or a 
prairie chicken, will lie until nearly trodden on, the bird showing 
by its action that its one thought is to escape observation, and its 
coloration and squatting attitude enabling it thus to escape 
observation, as Mr. Beddard puts it in his book on “ Animal 
Coloration,” “ absence of movement is absolutely essential for 
protectively coloured animals, whether they make use of their 
1 In passing I wish to bear testimony to the admirable work done by various 
members of the Thayer family in preserving birds and wild life—work so admirable 
that if those concerned in it will go on with it, they are entitled to believe anything 
in the world they wish about protective coloration ! 
