EVOLUTION OF INTELLIGENT BEHAVIOUR 165 
But I have satisfied myself by experiments with young birds, that 
(1) after experience with bees drones are avoided, and (2) that 
after similar experience drone-flies are also left untouched. 
Hence it seems that all three fall within the same generic image, 
the points of resemblance outweighing the differences in detail 
—as they do, indeed, with many men and women. 
Such examples of mimicry belong to what is known as the 
“ Batesian type ”—so called after H. W. Bates, who, in 1861, 
discussed its occurrence among Amazonian insects in the light 
of the theory of natural selection. There are, however, certain 
groups of insects which, although themselves “ protected,” 
possess common warning colours, causing them to resemble 
each other. These are sometimes classed under the head of 
“‘Mullerian mimicry ”—so called after Fritz Miiller, who, in 
1879, first offered an explanation of the facts based on the 
theory of natural selection. He suggested that such mutual 
resemblance is advantageous to both protected forms, since it 
lessens the number of those which are killed by young birds 
and other animals while they are learning by experience what 
to eat and what to leave. For, as the result of careful 
observation, Mr. Frank Finn concludes “that each bird has 
to separately acquire its experience, and well remembers what 
it has learnt,”—a conclusion with which, as already stated, my 
own observations are entirely in accord. There is therefore a 
certain amount of destruction of even well-protected forms 
by young and inexperienced birds. If, then, two such forms 
resemble each other, the acquisition of experience is thereby 
facilitated and the amount of destruction reduced, on the 
assumption that the two fall within the same generic image. 
Upholders of natural selection are not, indeed, at one in accept- 
ing this explanation, and further observation is unquestionably 
needed. It is not improbable, however, that common protective 
coloration, such as the banding of yellow and black, seen in such 
different forms as the caterpillar of the cinnabar moth and the 
imago of the wasp, is of mutual utility. The following experi- 
ment was made with young chicks. Strips of orange and black 
paper were pasted beneath glass slips, and on them mea 
