50 ANIMALCULA OP INFUSIONS. X, 



and animals into confideration, as they can fuf- 

 tain fo much lefs heat than feeds or eggs. How-, 

 ever, the rule has an exception in the germs of 

 the higheft animalcula ; for, whatever may be the 

 caufe, they can fupport lefs heat than the animals 

 themfelves. The animalcula die at io8^, but the 

 germs are not developed after 95 '^. We are un- 

 der the neceffity of admitting, therefore, that the 

 nature of the germs of the higher and lower clalfes, 

 is very different relative to their faculty of refifting 

 heat ; which is fully coincident with all I have 

 faid of vegetable feeds, and what fucceeds in 

 eggs. Peafe, lentils, wheat and lintfeed, for the 

 mod part, became fterile at 189° ; trefoil vege- 

 tated at 212° ; and M, Duhamel's wheat at 

 234° : and although the difference has not been 

 fo fenfible in the eggs of the animals mentioned 

 above, it is fufficiently perceptible in thofe of 

 another kind. The eggs depofited by certain 

 butterflies on the under fide of leaves, as well as 

 thofe that fome infects depofit to a northern af- 

 pect, perifti at 79°. Twenty degrees more will 

 hatch the eggs of other infects ; and that heat 

 even feems neceffary for their exclufion. Such 

 are thofe inferted by afih in the hard hide of 

 oxen, cows, or bulls ; of particular flies, that 

 infmuate them into the nofe or frontal fmus of 

 flieep, goats, or deer j and of others, which 



depofit 



