He SEMINAL VERMICULI. 23 
of heat the motion of vermiculi ceafed, and the 
degree of cold by which it is not relaxed. i 
have efteemed it moft effential to fupply this de- 
fect, in order to obtain arguments more conclu- 
five and decifive, and to learn if, with refpeét to 
heat and cold, the vermiculi are of a nature and 
conftitution much different, as M: de Buffon ima- 
gines, from the nature of other animals. 
Though the obfervations in Chapter I. do not 
feem to beftow that vigour of conititution fuffi- 
cient to enable them to refift cold, fince it feem- 
ed their motion decreafed with the decreafing 
heat of the atriofphere, fo that when the ther- 
mometer ftood at 36°, they continued moving on- 
ly an hour and a half: yet I refumed my expe- 
riments, refolving to extend them further, and 
fubject the femen to a degree of cold equal 
to freezing, and carefully obferve what fhould 
happen to the vermiculi. The femen firft ufed 
was that of the horfe. On the 14 of Janu- 
ary, it was expofed to freezing: the vermiculi 
could not be more vivacious ;_ their vivacity evi- 
dently diminithed; and in fixteen minutes all 
were motionlefs, though the femen was not froz- 
en: The cold becoming more intenfe on the 
#8, I repeated the experiment. The vermiculi 
became motionlefs in eleven minutes. The ther- 
mometer ftood at $° below freezing, but the fe- 
men was {till fluid. The experiments were often 
eVox. Il. C repeated 
