LECTURE VII. 
15 
The Tortoise seems more tenacious of the, 
vital principle than any other of the Amphibia.. 
Redi informs us, that in making some experiments 
on vital motion, he, in the beginning of Novem*: 
ber, took a land tortoise, and made a large 
opening in its skull, and drew out all the brain, 
washing the cavity, so as to leave not the smallest 
part remaining, and then, leaving the hole open,, 
set the animal at liberty. Notv/ithstanding this 
treatment, the Tortoise marched away, without 
seeming to have received the smallest injury/i'dt 
however closed its eyes, and never opened them 
afterwards. In a short space the hole of the 
skull was seen to close, and in about three days 
there was a complete skin covering the wound j 
and in this manner the animal lived, without the 
brain, for six months, walking about, and moving 
its limbs as before. Redi also cut off the head 
of a Tortoise, which lived twenty-three days after- 
wards 5 and the head itself continued to snap the' 
jaws for more than a quarter of an hour after 
its separation from the body. He repeated the 
experiment of taking out the brain upon several 
other Tortoises, both of land and fresh watery 
alLof wliich lived for a considerable space without 
