25@ ANIMAL REPRODUCTIONS, 
gular prerogative over the reft. In the firft 
place, the defective limbs begin fooner to be re- 
paired. A polypus, divided into many pieces, in 
a few hours begins to multiply into fo many 
other polypi; an earth or water worm requires a 
few days; a {nail or newt, on the contrary, re- 
quires feveral weeks, before beginning to repro- 
duce. Secondly, reproduction is much foon- 
er complete in the former. Only a few days 
are neceflary for a polypus ; worms require whole 
weeks ; the {nail muft have feveral months for 
repairing its head; anda year is not fufficient 
for the new limbs of a newt to grow as large as 
the old. ‘Thirdly, the fame animal, fo long as 
young, and the fibre confequently more tender 
and pliant, will reproduce the loft parts quicker. 
This I have feen in newts, and alfo in fnails, 
which will repair the fevered head in fix weeks, 
and much fooner, if young. Finally, reproduc- 
- tion is more tardy, as the natural foftnefs of the 
animal decreafes. We have a ftriking inftance 
of this in frogs. If, while {till tadpoles, but the 
limbs beginning to appear, their limbs fhould be 
amputated, by my own obfervations it is certain 
that they will be moft completely repaired. But 
she fame will not fucceed when the tadpole has 
affumed the figure of a frog: then it is never, or 
almoft never, that the trunk puts forth a new 
limb. Whence arifes fo great a difference in 
the — 
