42 THE NATURAL HISTORY OF THE COMMON CRAYFISH. 
what the young are; but if we examine it more closely, 
especially with a magnifying-glass, we see with pleasure 
that the little crayfish are already perfect, and resemble 
the large one in all respects. When the mother of these 
Jittle crayfish, after they have begun to be active, is quiet 
for a while, they leave her and creep about, a short way 
off. But, if they spy the least sign of danger,-or there is 
any unusual movement in the water, it seems as if the 
mother recalled them by a signal; for they all at once 
swiftly return under her tail, and gather into a cluster, 
and the mother hies to a place of safety with them, as 
quickly as she can. A few days later, however, they 
gradually forsake her.” * 
Fishermen declare that ‘‘ Hen Lobsters” protect their 
young in a similar manner.t Jonston,t who wrote in 
the middle of the seventeenth century, says that the little 
crayfish are often to be seen adhering to the tail of the 
mother. Roesel’s observations imply the same thing ; 
but he does not describe the exact mode of adherence, 
and I can find no observations on the subject in the 
works of later writers. 
It has been seen that the eggs are attached to the 
swimmerets by a viscid substance, which is, as it were, 
smeared over them and the hairs with which they are 
* “Der Monattich-herausgegeben Insecten Belustigung.” Dritter 
Theil, p. 836. 1755. 
+ Bell’s “ British Crustacea,” p. 249. 
+ “Joannis Jonstoni Historie naturalis de Piscibus et Cetis Libri 
quinque. TomusIV. ‘De Cammaro seu Astaco.fluviatili.’” 
