364 Address of A. R. Wallace at the Glasgow Meeting. 
at least the muzzle or the nose, are generally black. The ears 
and eyes are also often black ; and there is reason to believe that 
dark pigment is essential to good hearing, as it certainly is to 
perfect vision. We can therefore understand why white cats 
with blue eyes are so often deaf—a peculiarity we notice more 
readily than their deficiency of smell or taste. 
If then the prevalence of white coloration is generally accom- 
panied with some deficiency in the acuteness of the most im- 
itself in a wild state, while melanism does. The peculiarity of 
some islands in having all their inhabitants of dusky colors— 
as the Galapagos—may also perhaps be explained on the same 
sae" t 
more fully developed and more important to his welfare ne 
mere sense-acuteness, the lighter tints of skin, and bene 
Ss on the 
n islands. 
paid to the subject, and the relation of these two very Gl! 
classes of natural objects has been found to be more UNIV 
