If. SEMINAL VERMICULI. - g 
lar beinigs, could never have been exempted from 
uncertainty, I will even fay error, by preferring 
the compound microfcope to that of Leeuwen- 
hoeck. | 
Let us look back a moment to eftablifh the 
certainty of tails in the human feminal vermiculi. 
The faa is confirmed in fo convincing a manner’ 
by the experiment on talc, where the tails appear 
complete, and not confounded with the femen, 
as to put it beyond all doubt was there no 
other proof. However, we may obferve that fuch 
extreme circumfpection, and fo many precautions 
dre unneceflary to diftinguifh the tail in the ver- 
miculi of many animals, when Leeuwenhoeck’s 
Microfcope is ufed. 
To the contraCtion and entire difappearance of 
the tails, which Buffon fays he obferved when the 
vermiculi remained long in the fémen after it 
éame from the animals body, I can oppofe no- 
thing except that in all my obfervations, which 
have been innumerable, the reverfe was uniform- 
ly feen. The vermiculi conftantly preferve this 
member not only while alive, but long after 
death ; and it does ndt begin to fpoil or be de- 
ftroyed till the vermiculi themfelves arrive at the 
fame ftate. Further, neither the maceration of 
the dead bodies by boiling, nor is freezing fuffi- 
tient to deftroy their {tructure or figure. Vine- 
gar itfelf and urine, fluids which inftantaneouily 
A 3 deftroy 
