210 THE HORSE FOOT CRAB. 
its limbs that exposure of the under side to the attacks of 
fishes would soon end its career. In short it must keep its 
carapace "right side up with care," if it would care to live. 
I must now mention another functional metamorphosis 
which seems to me of a very remarkable character. So 
great is the difference in form between the anterior feet of 
the female, and the same feet in the male, that the very 
children on the shore lines at once in this way distinguish 
the sexes. In the female this limb is long, slender, and 
weak ; in the male short, stout and ventricose. Intended for 
strong holding, their nip is like that of a vice. Their use is 
to hold on to the carapace of the female, so that the male 
may retain his position as the pair come up in the breeding 
season. And so strong his hold that no violence of storm, 
or attack of rival suitors, can displace him. Well does the 
fisherman know this, as he stands in the water ready to spear 
the female as she comes up in nuptial embrace. He is only 
concerned to catch the female, for it would need some force 
to separate the two. Now functionally, this stout foot, "or 
hand," as the fishermen call it, has no use in early life. The 
Horse Foot Crab has its period of puberty ; this is its adult 
stage. But judging from the size of the males when they 
couple, which is pretty uniform, and their actual rate of 
growth, I think that the puberty of Limulus cannot come 
before the third or fourth year. And it would not surprise 
me if the latter figure should prove the minimum age. 
However this is the point— it is not until that age of pu- 
berty is reached that the male undergoes its last metamor- 
phosis. It then has a moult, from which it emerges, having 
received its large claws, or literally, its nuptial hands. 
What change there may be on the emotional side wlio can 
tell, when master Limulus assumes the toga virilis and is old 
enough to "propose." This may be asserted of these very 
decorous and monogamous people, that among them prema- 
ture marriages are unknown, for however soon the lady may 
be ready to give her heart, not until maturity of age can the 
gentleman possibly extend to her his hand. 
