allowed itself
to undergo severe Degeneration.

In dealing with the Hermit-crab, in short, we are dealing with a case of
physiological backsliding. That the creature has lost anything by this
process from a practical point of view is not now argued. It might
fairly be shown, as already indicated, that its freedom is impaired by
its cumbrous exoskeleton, and that, in contrast with other crabs, who
lead a free and roving life, its independence generally is greatly
limited. But from the physiological standpoint, there is no question
that the Hermit tribe have neither discharged their responsibilities to
Nature nor to themselves. If the end of life is merely to escape death,
and serve themselves, possibly they have done well; but if it is to
attain an ever increasing perfection, then are they backsliders indeed.

A zoologist's verdict would be that by this act they have forfeited to
some extent their place in the animal scale. An animal is classed as a
low or high according as it is adapted to less or more complex
conditions of life. This is the true standpoint from which to judge all
living organisms. Were perfection merely a matter of continual eating
and drinking, the Am[oe]ba--the lowest known organism--might take rank
with the highest, Man, for the one nourishes itself and saves its skin
almost as completely as the other. But judged by the higher standard of
Complexity, that is, by greater or lesser adaption to more or less
complex conditions, the gulf between them is infinite.

We have now received a preliminary idea, although not from the study of
a true parasite, of the essential principles involved in parasitism. And
we may proceed to point out the correlative in the moral and spiritual
spheres. We confine ourselves for the present to one point. The
difference between the Hermit-crab and a true parasite is, that the
former has acquired a semi-parasitic habit only with reference to
_safety_. It may be that the Hermit devours as a preliminary the
accommodating mollusc whose tenement it covets; but it would become a
real parasite only on the supposition that the whelk was of such size as
to keep providing for it throughout life, and that the external and
internal organs of the crab should disappear, while it lived henceforth,
by simple imbibition, upon the elaborated juices of its host. All the
mollusc provides, however, for the crustacean in this instance is
safety, and, accordingly in the meantime we limit our ap