ike a man carrying
a dog-house. I attempted to pull him out of his lodging, and he
was so firmly fastened to the interior by hooks on his belly that
he held on until he was torn asunder. His abdomen is soft and pulpy
and without protecting plates, as have other crabs, and he survived
only by his childhood custom of stealing a univalve abode, though
he murdered the honest tenant. In one I saw the large pincher of the
crab so drawn back as to form a door to the shell as perfect as the
original. When he felt growing pains the hermit-crab unhooked himself
from his ceiling and migrated in search of a more commodious dwelling.

Interesting as were these habits of the cenobite crustacean, his
keeping a policeman or two on guard on his roof, and moving them to
his successive domiciles, was more so. These policemen are anemones,
and I saw hermit crab-shells with three or four on them, and one even
in the mouth of the shell. When the anchorite was ready for a new
shell, he left his old one and examined the new ones acutely. Finding
one to suit his expected growth, he entered it belly first, and
transferred the anemone, by clawing and pulling loose its hold,
to the outside of his chosen shell. How skilfully this was done may
be judged by the fact that I could not get one free without tearing
the cup-like base which fastened it. The anemone assisted in the
operation by keeping its tentacles expanded, whereas it withdrew
them if any foreign object came near. The stinging cells of the
anemone prevent fishes from attacking the hermit, and that is the
reason of his care for the parasite. It is the commensalism of the
struggle for existence, learned not by the individual crab, but by
his race. Some crabs wield an anemone firmly grasped in each claw,
the stinging nematocysts of the parasite warding off the devilish
octopus, and the anemone having a share of the crab's meals and the
pleasure of vicarious transportation. The anemone at the mouth of
the shell keeps guard at the weakest spot of the hermit's armor.

These sea-anemones themselves are mysterious evidences of the gradual
advance of organisms from the slime to the poem. They are animals,
and attach themselves by a muscular base to the rocks or shells,
or are as free-swimming as perch. I saw them two feet in diameter,
seeming all vegetable, some like chrysanthemums and some resembling
embroidered pin-cushions. They were of many colors, and are of the
coral family.

In this won