460 
THE ROBBER-CRAB. 
Its exposed claws and head being reinforced, as it were, by handsome scaled armor. These 
portions are extremely hard, and of a bright brick color. Once ensconced in the shell, which 
in its stoutness is like a castle, the armored front that Hermit presents may defy any enemy. 
But strategy sometimes succeeds. Once the creature unconsciously peeps too far away from 
his sally-port, he is outflanked, and forced to give battle outside his portcullis. Few objects 
are more entertaining. The great Land Hermits are especially so. They never go to the sea, 
but live in dry places, where they burrow under stones or logs. 
The Diogenes Hermit-crab is a handsome and rather large species that inhabits Brazil 
and the West India Islands. 
It occupies the shells of various mollusks, mostly, however, giving the preference to some 
large species of turbo ; and Mr. Bennett mentions that he possesses an unique shell which he 
found on the branch of a tree, having been taken from the sea by one of these crabs. While 
living, the Diogenes gives out a very unpleasant odor ; and as the crabs are in the habit of 
assembling in great numbers, the aggregate effect is rather overpowering. They gather 
together at the foot of trees or under bushes or brushwood, and even contrive to clamber up 
the branches or the trunks of trees, drawing themselves up by their powerful claws and limbs, 
and caring little for the heavy burden which they bear on their backs. They have the power 
of producing a curious noise, something like the croak of a frog alternating with sounds as if 
of drawing water through the lips. 
They are active and voracious beings, and feed with equal avidity on animal and vegetable 
substances. They prefer animal food, such as fish, crabs, and, indeed, almost any kind of 
flesh, but they will greedily eat yams, cocoa-nut, and other fruits. They are timid creatures, 
croaking when disturbed, and seldom attempting to fight, but draw themselves smartly within 
their homes as soon as they feel alarmed. They are mostly nocturnal in their habits ; and as 
they bring a large supply of shells to land, and are very fastidious about their accommodation, 
a great heap of empty shells is to be seen upon the shore, and there is a continual rattle during 
the night as the creatures knock the shells about in their movements. 
In all these creatures the larger claw is very much developed; so that when the crab has 
withdrawn into the shell, the claw lies over the entrance and closes it like a living door, which 
has the further advantage of being used as an offensive weapon. The footstalks on which the 
eyes are set, are moderately long, stout, and jointed, and enable their possessor to see in all 
directions. The color of this species is reddish-brown, spotted thickly with black. 
A common species at Tortugas is the Diogenes. In an old wooden building attached to 
the Post, we had a room for the examination and care of natural objects. Under this building 
the Diogenes lived, several of them. One exhibited symptoms of restlessness, and after sev- 
eral days of fruitless wandering in and out of our room, he ultimately came to a halt, and a 
determination to scale the corner of a bookcase, where a saucer of fresh water chanced to be. 
With his heavy Trochas shell hanging like a soldier’s equipments from his back, he reached, 
with tolerable celerity, the shelf, or top, of the bookcase. Here he sipped, and moistened his 
gills, and cautiously commenced the return. This he accomplished much as any climbing 
mammal would, hand over hand, with the body hanging behind. This crab repeated the feat 
often, apparently for the purpose of moistening its gills. It became quite tame ; would take 
food from the hand. It was sent north to Massachusetts, where a land Hermit is a strange 
thing. There it moulted twice, but though it was protected under glass, it died after a year’s 
captivity. Several others were placed among loose packages in a box and sent north, but the 
strongest had battled with the others and destroyed them, leaving nothing but dried shells. A 
small specimen of the same had picked up a cast-off clay pipe, and this we cherished for a 
time as a comical example. The bodies of these Hermits are soft and wonn-like. 
Closely allied to the hermit-crabs, we find a very remarkable creature, called from its habits 
the Robber-crab. It is also known by the name of Purse-crab. The habits of this creature, 
which will presently be described, are most remarkable, and there are several singular peculi- 
arities of structure. The abdomen, for example, is no longer soft as in the hermits, but is 
covered above with strong plates, which overlap each other like those of the lobster’s tail. 
The under surface of the abdomen is soft and membranous. This is one of the Crustacea that 
