searching gaze of the zoologist, its expedient is
certainly not one to be commended. To the eye of Science its sin is
written in the plainest characters on its very organization. It has
suffered in its own anatomical structure just by as much as it has
borrowed from an external source. Instead of being a perfect crustacean
it has allowed certain important parts of its body to deteriorate. And
several vital organs are partially or wholly atrophied.

Its sphere of life also is now seriously limited; and by a cheap
expedient to secure safety, it has fatally lost its independence. It is
plain from its anatomy that the Hermit-crab was not always a
Hermit-crab. It was meant for higher things. Its ancestors doubtless
were more or less perfect crustaceans, though what exact stage of
development was reached before the hermit habit became fixed in the
species we cannot tell. But from the moment the creature took to relying
on an external source, it began to fall. It slowly lost in its own
person all that it now draws from external aid.

As an important item in the day's work, namely, the securing of safety
and shelter, was now guaranteed to it, one of the chief inducements to a
life of high and vigilant effort was at the same time withdrawn. A
number of functions, in fact, struck work. The whole of the parts,
therefore, of the complex organism which ministered to these functions,
from lack of exercise, or total disuse, became gradually feeble; and
ultimately, by the stern law that an unused organ must suffer a slow but
inevitable atrophy, the creature not only lost all power of motion in
these parts, but lost the parts themselves, and otherwise sank into a
relatively degenerate condition.

Every normal crustacean, on the other hand, has the abdominal region of
the body covered by a thick chitinous shell. In the Hermits this is
represented only by a thin and delicate membrane--of which the sorry
figure the creature cuts when drawn from its foreign hiding-place is
sufficient evidence. Any one who now examines further this half-naked
and woe-begone object, will perceive also that the fourth and fifth pair
of limbs are either so small and wasted as to be quite useless or
altogether rudimentary; and, although certainly the additional
development of the extremity of the tail into an organ for holding on to
its extemporized retreat may be regarded as a slight compensation, it is
clear from the whole structure of the animal that it has