29 
the only known recent species belonging to this genus. 
Here are also specimens of the Freshwater Crabs 
(Thelphusce), which live in the rivers and streams of 
Italy, and the south of Europe, and are also found in 
Asia and America ; they are capable also 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 medicinal virtues, and is fre¬ 
quently 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 cylindri¬ 
cal 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 
his hole, he closes the entrance with his claw, one of 
which, sometimes the right, sometimes the left, is com¬ 
monly 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 rapidity of the motions of these Crus¬ 
tacea, is particularly applicable 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, which inhabit bivalve 
shells, and were supposed by some of the ancients to be 
consentaneous inmates with the animal, bound by mutual 
interest. The Painted or Land Crabs (Gecarcinus), 
live in holes in the earth, especially near burying- 
grounds, and only go to the sea during the breeding 
season; their flesh is considered a delicacy, but some¬ 
times proves deleterious. Besides the preceding, there 
are 
ROOM IX. 
Nat. Hist. 
