346 ANIMAL REPRODUCTIONS, 
M. Adanfon feems to reproach me with ufing 
{nails of too fmall a fize ; he remarks, that the 
fmall fpecies which were ufed muft have deceived - 
me, from their great alacrity in eluding the edge 
of the knife. Neverthelefs, 1 can affirm, that I 
have operated on the imall {pecies as eafily as on 
the middle fized, and even the largeft. _ But we 
exaggerate the alertnefs of {nails, in faving their 
heads; for, abftinence during feveral days, 
and immerfion in water, undoubtedly weaken. 
them, and, to a certain degree, diminifh the 
celerity of their motions. Befides, if fmall 
fhails were mutilated, it was only becaufe I 
reafonably prefumed, that the wonderful repro- 
duction which I wifhed to behold would be ac- 
complifhed more eafily, or in fhorter time, than 
in the largeft {nails. . However, experiments on 
the largeft {pecies have not been omitted ; and the 
fuccefs fhall be related. 
To terminate this anfwer to the objections of 
our celebrated Pyrrhonift, I fhall here fubjoin an 
extract from a letter that 1 wrote to him 2r 
january 1778. 
‘If it was in the compafs of my power, my 
© dear and illuftrious friend, I fhould make the 
* experiments you defire on {nails. But, in truth, 
“I do not think that any thing can be done more 
* ftridtly demonftrative than ‘what has been fo 
* well executed by my friend Signor Spallanzani ; 
‘ and 
