* ANIMAL REPRODUCTIONS, § 319 
ple continue oppofing-to the Pavian experiments, 
thofe which they fuppofe contradictory or appa 
rently confuting them. I have been induced 
myfelf to repeat the learned Profeffor’s inveftiga- 
tions, owing to this conflict of experiments, 
which has continued nine years. From the ac- 
count which I proceed to give, the impartial pub- 
lic will judge of the confidence that it deferves. 
The fpecies of {nail on which I operated, is of 
a middle fize, and frequent in the fields or in 
gardens after a rainy day; numbers then aban- 
don their dark retreats, and ina fhort time one 
may collect hundreds. The fhell of fome is yel. 
low, or yellowifh ; on that of others are circular 
black or brown fafciee, 
It is by no means an eafy matter to decapitate 
a fnail, for the moment it feels the inftrument, 
it fuddenly retires into the fhell. Thus it is evi- 
dent, that we may fuppofe a {nail is decapitated, 
when only a portion of the integuments is cut off. 
To avoid deception, I have ufed feveral precau- 
tions, ‘The {nail is allowed to extend as much . 
as poflible, and an additional extenfion is pro- 
cured by immerfing the animal in water. The 
inftrument is frequently prefented. before ftriking 
the blow; and I never efteem the operation com- 
plete unlefs the head is obtained entire, with the 
~ four horns fully difplayed, and alfo the mouth, 
which may always be recognifed by the opening 
' of 
