other feet are copies or adaptations. This instrument, as part of the
original outfit given to the pioneers of the brainy, backboned, and
four-limbed races, when they were sent out to multiply and replenish the
earth, is surely worth considering well. It consists essentially of a
sole, or palm, made up of small bones and of _five_ separate digits,
each with several joints.

[Illustration: AN AUTHENTIC STANDARD FOOT.]

In the hind foot of a frog the toes are very long and webbed from point
to point. In this it differs a good deal from the toad, and there is
significance in the difference. The "heavy-gaited toad," satisfied with
sour ants, hard beetles, and such other fare as it can easily pick up,
and grown nasty in consequence, so that nothing seeks to eat it, has
hobbled through life, like a plethoric old gentleman, until the present
day, on its original feet. The more versatile and nimble-witted frog,
seeking better diet and greater security of life, went back to the
element in which it was bred, and, swimming much, became better fitted
for swimming. The soft elastic skin between the fingers or toes is just
the sort of tissue which responds most readily to inward impulses, and
we find that the very same change has come about in those birds and
beasts which live much in water. I know that this is not the accepted
theory of evolution, but I am waiting till it shall become so. We all
develop in the direction of our tendencies, and shall, I doubt not, be
wise enough some day to give animals leave to do the same.

It seems strange that any creature, furnished with such tricky and
adaptable instruments to go about the world with, should tire of them
and wish to get rid of them, but so it happened at a very early stage.
It must have been a consequence, I think, of growing too fast. Mark