ROOM IX.] NATURAL HISTORY. 27 
live in the rivers and streams of Italy, and the south of 
Europe, and are likewise found in Asia and America; 
they are capable of existing a considerable time out of the 
water. One species, peculiar to the south of Europe and 
the Levant, (Le Cancre de riviere of Rondeletius,) enjoyed 
great celebrity amongst the Greeks, for its supposed me¬ 
dicinal virtues, and is frequently represented on the coins 
of Agrigentum with the utmost accuracy. In this Case 
are likewise some Crabs peculiar to hot countries, which 
are remarkable for the rapidity of their motions, and other 
peculiarities. They live in holes, usually near the sea¬ 
shore or in the neighbourhood of water ; these holes are of 
a cylindrical form, oblique, and very deep, and several of 
them are generally found near together, but each hole con¬ 
tains only one inhabitant. When the animal of one of the 
genera belonging to this family ( Gelasimus ) is in its hole, 
it closes the entrance with its claw, one of which, some¬ 
times the right, sometimes the left, is commonly much 
larger than the other. These Crustacea have also a 
singular habit of holding up the large claw in front of the 
body, as if they were beckoning to some one at a distance, 
whence they have acquired the name of Calling Crabs 
(Cancer vocans , Linn.). What has been said of the rapid¬ 
ity of the motions of these Crustacea, is particularly ap¬ 
plicable to those of the genus Ocypode, which hide in holes 
in the sand on the sea-shore during the day, and leave 
them at sun-set. This case also contains specimens of the 
genus Pinnotheres, a very small race of Crustacea, inhabit¬ 
ing bivalve shells, and supposed by some of the ancients 
to be consentaneous inmates with the molluscous animal, 
and attached to it by mutual interest. The Painted or 
Land Crabs ( Gecarcinus ), live in holes in the earth, espe¬ 
cially near burying-grounds, and only go to the sea during 
the breeding season; their flesh is considered a delicacy, but 
it sometimes proves deleterious. Besides the preceding, 
there are specimens of the Globular Crabs ( Leucosia ); Sea 
Spiders ( Leptopodia ), with their very long legs ; Crested 
Crabs ( Calappa ), having the front part of the claws raised 
into a crest, and the hinder part of the shell projecting so 
as to cover the legs; and lastly, those Crabs which have 
the two hinder pairs of legs placed on their back, (JDorippe ), 
and the Death's-head Crabs ( Dorima ). 
