Aug., 1892. colours and coloration in animals. 
175 
wonderful individuality, a character which is usually taken to 
indicate purposefulness : thus the palate of the Orang-outang is 
black, that of the Chimpanzee, flesh-colour. Such a difference 
in other cases is sought to be explained by natural selection, 
but if no such explanation is possible here, is it not probable 
that many forms of external colour modifications may exist 
without such explanation ? Then, again, there are the deep 
sea animals : the abysses of the ocean are profoundly dark, as 
is shown both by direct experiment and also by the absence 
of plant-life ; the majority of the animals inhabiting these 
depths are blind, and yet, as a rule, they are of brilliant 
coloration, the sea-urchins being dark purples and browns, 
the crustaceans often of brilliant scarlet, and the fishes 
commonly black. Now, as it is an enormously long time since 
the ancestors of these animals migrated from shallow waters 
into the abysses, according to the commonly received theory, 
the coloration originally of use ought now, having for so long 
been useless, to have disappeared. But it has not. Since, 
then, natural selection has had no effect in this case, need we 
suppose that agent essential to account for the coloration of 
shallow water forms ? 
We turn now to another consideration urged by Mr. 
Beddard: in many cases the object of coloration seems 
evident enough to human ideas, yet we ought to receive the 
explanation with doubt, just because we are human and 
cannot view the matter from the point of the animals 
concerned, and especially should we suspend our judgment if 
there are any facts opposed to the theory. Thus, the marine 
animals—known as the pelagic fauna—which live near the 
surface of the sea, are generally quite transparent, except for 
the contents of their stomachs which are often vellowish, and 
resemble a small piece of sea-weed. These animals, at first 
sight, seem perfectly protected against enemies, but, asks Mr. 
Beddard, of what use is their invisibility in the case of a 
school of whales or a shoal of fish which simply strain the 
water of such food as it contains without pausing to examine 
carefully what is there ? Again, the green iguana lying 
along the branch of a tree would seem to be another perfect 
example of protective coloration, yet there is a species in Sta. 
Lucia which, in spite of its colour, is easily caught by dogs, 
as these animals hunt by smell and not by sight; against 
such foes, and they will be many, the most perfect protective 
coloration would be useless. 
Another consideration of primary importance in discussing 
the object of resemblances among animals is their power ot 
vision ; we judge of the efficiency of disguise in an animal 
