338 NATURAL SCIENCE. May, 
Tactile sensibility scarcely exists in the internal organs, where it 
would be worse than useless. It is most delicate in the tip of the 
tongue, which keenly examines food by touch as well as by taste, and 
in the tips of the fingers, which serve as tactile and manipulative 
organs. The face, though including highly important organs, does. 
not need so discriminative a perceptiveness as the tongue and finger, 
and accordingly possesses much less even in the lips and the tip of 
the nose, where its tactile sensibility is finest. The body and limbs, 
which have never needed a highly discriminative sense of touch, have 
never evolved such keen sensibility, so far as is known, and the Neo- 
Darwinian has, therefore, no need to adopt the suggestion of degene- 
racy under panmixia so superfluously made on his behalf. The back 
of the head and body has less perceptive power than the front, where 
it has been more needed, since we move in a forward direction, and 
meet or touch objects in front of us more often than objects in the 
rear. Great part of our tactile equipment dates back to very remote 
eras. Tongue, fingers, toes, lips, and nose must have evolved special 
tactile powers even before our ancestors had arrived at the Simian 
stage of evolution; and in passing through foliage, branches, and 
thorny bushes a fairly developed sense of touch in the face would be 
far more serviceable than in the back of the head, and the chest and 
limbs might well become somewhat more discriminative than the 
back. 
While the relative sensibility of parts can in the main be 
accounted for by the Neo-Darwinian, it must be freely admitted that 
we cannot fully and decisively explain every detail, every minor modi- 
fication, and every gradation, by the principle of the survival of the 
fittest. We may be unable, for instance, to explain why the thigh and 
fore-arm are less sensitive in the middle than near the end, or why 
the skin over the malar bone is less discriminative than other parts of 
the cheek, or why the tip of the nose retains a measure of tactile 
perceptiveness exceeding that of the palm of the hand; but our 
failure to unravel and clearly demonstrate every obscure cause 
of the minor facts of variation and evolution proves nothing. Even 
if we accept Mr. Spencer’s view of the inadequacy of Neo- Darwinian 
factors, we still have to inquire whether use-inheritance will fill the 
gap, or whether it is equally or still more inadequate to afford the 
desired explanation. Does it help us to account for the fact that the 
tip of the nose is four-and-a-half times as discriminative as the back 
of the hand?? Is it reasonable to suppose that the nose comes into. 
contact with objects far more frequently than the back of the hand 
does? Does it touch things just about as often as the third or lowest. 
joints of the fingers, three times as often as the lower part of the 
2 The numbers in these comparisons might fairly be squared so as to represent 
the relative number of separate tactile areas in a given space instead of linear dis- 
tances. Thus estimated, the tip of the nose is twenty times as sensitive as the back 
of the hand. * 
