REPRODUCTION. 587 



of being multiplied by artificial divisions, each 

 segment having the power of supplying others, 

 and containing within itself a kind of separate 

 and individual vitality. 



A power of more partial regeneration of muti- 

 lated parts by new growths, which is very 

 analogous to that of complete reproduction, 

 exists in the higher orders of animals, though it 

 does not extend to the entire formation of two 

 individuals out of one. The claws, the feet, and 

 the antennae of the Crustacea, and the limbs of 

 the Arachnida, are restored, when lost, by a 

 fresh growth of these organs. If the head of a 

 Snail be amputated, the whole of that part of 

 the animal, including the telescopic eyes, and 

 other organs of sense, will be reproduced. Even 

 among the Vertebrata we find instances of these 

 renovations of mutilated parts ; as happens w ith 

 respect to the fins of fishes : for Broussonet 

 found that in whatever direction they are cut, 

 the edges easily unite ; and the rays themselves 

 are reproduced, provided the smallest part of 

 their base has been left. The tails of Newts, 

 and of some species of Lizards, will grow again, 

 if lost : and what is more remarkable, the eyes 

 themselves, with all their complex apparatus of 

 coats and humours, will, if removed, be replaced 

 by the growth of new eyes as perfect as the 

 former. We have seen that the teeth of Sharks 

 and other fishes are renewed with the utmost 



