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of swimming feet into feathery plumes, which now wave around a 
new aperture which serves asa mouth. It began life, I say, on 
the same footing as a shrimp, but the latter passed it in the race, 
and we can with difficulty recognise it as a member of the same 
order. . 
There does not seem room for doubting that the Hermit Crab 
occupies a niche in Nature’s temple not destined for him. At some 
former period one might imagine that his indolent ancestors, in 
order to protect themselves better, ‘‘hit on the happy device of 
utilizmg the habitations of the molluscs which lay around them 
in plenty, well built, and ready for immediate occupation” 
(Drummond). Ceasing to care for its own protection, it has 
gradually lost what was given it for that purpose, and its shell and 
some important organs have altogether or well-nigh disappeared. 
The Hermit Crabs are like men who have ceased to construct houses 
using instead the caves in the rocks. ‘To the eye of Science,” 
says Mr. Drummond, ‘‘ its sin is written in the plainest characters 
on its own organization.” 
But now, this degenerate member of crab society harbours in 
his own tissues a still more degenerate crustacean, whose downfall 
has been thorough and complete. The representation of Sacculina 
(diagram) would not be taken, I venture to say, by any non- 
naturalist as that of an animal atall. It is in fact a mere 
membranous bag with no organs of sense whatever, full of eggs, 
and having this bunch of tortuous organs, by means of which, as 
with roots, it burrows into the tissues of its host. ‘ It possesses 
neither legs, nor eyes, nor mouth, nor throat, nor stomach ; . 
; it is a typical parasite. When we enquire into 
the life history of this small creature, we unearth a career of 
degenerency all but unparalleled in Nature” (Drummond). For it 
begins life, as we have said, as a Nauplius, in a form little below 
_ that of its host, but at a certain stage in its history it shrinks from 
the struggle of life, and forces others to provide for it. 
There are certain people who sometimes talk glibly of what 
they call the Laws and arrangements of Nature, and say that we 
cannot do better than imitate them—people who say society ought 
to be constituted like that of bees or ants—people who would 
degrade the dearest relations of life to such as exist among the 
lower animals. I wonder if they are conscious of the results 
. which would ensue, if their ideas were consistently acted upon. 
There is never a crime that man committed, which might not 
be justified by examples from nature. Theft, robbery, slavery, 
war, murder—we can see them all going on around us daily in the 
“arrangements” of the animal kingdom. The human parasite 
might readily justify his unjustifiable meanness, if we allowed him 
