ELEDONE. 475 
How long Eledone lives is not known. However, 
from the fact that during the early spring quite young 
specimens occur—probably hatched from the previous 
summer’s spawn—together with many stages between half 
and full grown specimens, they probably live several 
years under natural conditions. At present nothing is 
known as to their rate of growth, or the size at which 
sexual maturity is reached. Hledone is an extremely 
delicate animal, and rapidly suffers if the tank in which 
it is placed has-not a good and constant supply of sea 
water. Hence it is practically impossible to observe it 
alive elsewhere than at the Marine Biological stations. 
Confinement affects it in various ways. For instance, 
although it was found, on dissecting several [ledones 
which had been kept in captivity for some weeks, that 
the ink sac was full of ink; yet after the violent ejection 
of ink which occurred when the animals were first caught, 
and one or two very slight subsequent discharges, no ink 
was ever again poured out. Even when being killed, no 
ink was ejected, although the body was convulsed, and 
the animal appeared to make a great effort to discharge 
the secretion. 
Foop. 
As Hledone is taken in both crab and lobster pots, 
probably it eats both these Crustaceans. However, when 
kept in tanks, it is generally fed on crabs, and crab 
remains alone were found in the gut of numerous 
specimens which were examined. It has been known to 
attack and devour the Norway lobster, and will take 
prawns or shrimps when they are placed in the same tank. 
Preferably it takes the Edible Crab, Cancer pagurus, but 
Portunus depurator is also taken, and Carcinus moenas. 
Eledone sometimes stalks its food, creeping after the 
