34 THE NATURAL HISTORY OF THE COMMON CRAYFISH. 
mences, the crayfish rubs its limbs one against the 
other, and, without changing its place, moves each 
separately, throws itself on its back, bends its tail, 
and then stretches it out again, at the same time vibrat- 
ing its antenne. By these movements, it gives the 
various parts a little play in their loosened sheaths. 
After these preparatory steps, the crayfish appears to 
become distended; in all probability, in consequence of 
the commencing retraction of the limbs into the interior 
of the exoskeleton of the body. In fact, it has been 
remarked, that if, at this period, the extremity of one of 
the great claws is broken off, it will be found empty, 
the contained soft parts being retracted as far as the 
second joint. The soft membranous part of the exo- 
skeleton, which connects the hinder end of the carapace 
with the first ring of the abdomen, gives way, and the 
body, covered with the new soft integument, protrudes ; 
its dark brown colour rendering it easily distinguishable 
from the greenish-brown old integument. 
Having got thus far, the crayfish rests for a while, and 
then the agitation of the limbs and body recommences. 
The carapace is forced upwards and forwards by the pro- 
trusion of the body, and remains attached only in the 
region of the mouth. The head is next drawn backwards, 
while the eyes and its other appendages are extracted from 
their old investment. Next the legs are pulled out, either 
one at a time, or those of one, or both, sides together. 
Sometimes a limb gives way and is left behind in its sheath, 
