566 Mr. A. H. Thayer on 
The act of flight tends to obliterate pattern, by the 
too quick substitution of one colour for another before the 
eye. A black-and-white butterfly, therefore, tends to 
look simply grey in flight. 
It is not necessary to conceive that a bird must find the 
imitation flower on its proper plant, if the flower represent 
a type common in the neighbourhood. <A vast majority of 
butterflies, including most members of Mimicry groups, 
have the common dark wing-tips of the /uscouws colour 
which causes this portion to seem lacking from the butter- 
fly, leaving the lighter-coloured parts to represent a more 
flower-like form. The white dots, so common on these 
black tips, surprisingly aid the representation of space 
below the flower by supplying the average sharp details 
that are to be seen down in the shady under-spaces,— 
little glints of light on twigs, ete..—and their dark ground 
is rendered additionally transparent in appearance by 
iridescence. 
If the foregoing arguments prove that the so-called 
Warning-colours commonly cited do not exist mainly to 
make their wearer conspicuous, it does not follow that 
they may not still serve secondarily as Warning-colours. 
When, for instance, they happen to fail to conceal, they 
may then serve to warn. My main point is that they 
first of all conceal. I suspect that the same principles 
apply to striped wasps and hornets, and many other 
insects called conspicuous. The yellow pattern unmistak- 
ably allies their appearance to the pollen-covered flower- 
interiors, making them far less conspicuous than an 
unmixed need to be seen would have them. Yet when 
seen, they may well profit by the pattern’s recognizability. 
Can any one, once shown, as I here show, that butterflies’ 
patterns are not intrinsically the thing to make the wearer 
conspicuous, and shown that they ae wonderful representa- 
tions of the flower-scenery I describe, believe that Natural 
Selection has bungled, and wasted design of the most 
intricate kind? No, it is the beauty of the whole thing 
that absolute fitness is the goal of all changes by Natural 
Selection :—is, in fact, the only motive-power ; changing 
all forms steadily toward itself. 
We see, then, that butterflies are imitation flowers, or 
pictures of flower and background. This has escaped the 
eye of zoologists. They see that fish wear representations 
of under-water scenery; that forest animals are forest- 
