424 
plint's natural htstoet. 
[Book IX. 
manner of snakes, throw off old age, and renew their coverings. 
While other animals swim on the water, cray-fish float with a 
kind of action like creeping. They move onwards, if there is 
nothing to alarm them, in a straight line, extending on each 
side their horns, which are rounded at the point by a ball 
peculiar to them ; but, on the other hand, the moment they 
are alarmed, they straighten these horns, and proceed with 
a sidelong motion. They also use^^ these horns when fight- 
ing with each other. The cray-fish is the only animal that 
has the flesh in a pulpy state, and not firm and solid, unless 
it is cooked alive in boiling water. 
(31.) The cray-fish frequents rocky places, the crab^^ spots 
which present a soft surface. In winter they both choose 
such parts of the shore as are exposed to the heat of the sun, 
and in summer they withdraw to the shady recesses of deep 
inlets of the sea. All fish of this kind suffer from the cold of 
winter, but become fat during autumn and spring, and more 
particularly during the full moon ; for the warmth of that lumi- 
nary, as it shines in the night, renders^^ the temperature of the 
weather more moderate. 
CHAP. 51. THE VAEIOTJS KINDS OF CEABS ; THE PINNOTHERES, 
THE SEA UECHIN, COCKLES, AND SCALLOPS. 
There are various kinds of crabs,^"^ known as carabi,^ astaci,^* 
^3 Aristotle, Hist. Anim. B. viii. c. 4, states to a similar effect. 
Aristotle, loc, cit., and ^lian, Hist. Anim. B. ix. c. 25, state to the 
same effect. 
65 Hardouin says, that this must he only understood of the kind of crab 
known as the astacus that being the one mentioned by Aristotle, in 
the passage from which Pliny has borrowed. 
He mentions, in B. ii. c. 41, the effect which the rays of the moon 
have upon the growth of shell-fish. 
67 Aristotle, Hist. Anim. B. iv. c. 2, has a somewhat similar passage. 
The kinds of crabs are numerous, and not easily to be enumerated. 
First, there are those known as maia^, then the paguri, which are also 
called * heracleotici and, after them, the river crabs. There are others, 
again, of a smaller size, and which, for the most part, are known by no 
name in particular." 
^ This is, no doubt, the cray-fish, the same animal that has been caUed 
the " locusta*' in the preceding Chapter. Aristotle states, B. iv. c. 8, that 
the carabus has the thorax rough and spiny. It is most probable, that it 
is from this name that our word " crab " is derived. 
Cuvier says, that the astacus, which is very accurately described by 
