[ 479 1 
about a Line. Both Pieces periffied in about Twenty- 
four Hours, the Tail firft, and the Head after. As 
to the Body, it continued to move almoft as if I had 
not made the Operation. I have even feen, what 
appeared to me extremely remarkable, that, a few 
Moments after, it thruft itfelf into the Mud, making 
life of its anteriour Extremity, as of a Head, to bore 
its Way through. I have repeated this Experiment 
with the fame Succefs : So that I am confident I may 
aflert, that there are in the Body of thefe Worms at 
leaft Two Points, where, if they are cut, the Repro- 
duction will not take Place. The one is about the 
Fifth or Sixth Ring from the Head 5 the other, at an 
equal Diftancc from the Extremity of the Tail. Is 
not, perhaps, the Condition of the great Artery in 
thefe Two Parts the Caufe of it? This indeed feems 
to me probable; remembering, however, that what 
I have juft faid only relates to the Two Pieces de- 
tached from thofe Extremities ; for, as to the inter- 
mediate Body, it not only continues to live, but it 
is even not long before it regains all that was taken 
from it. Where then does the Principle of Life 
rcfide in fuch Worms, as, after having their Heads 
cut off, ftill (hew not only the fame Motions, but 
even the fame Inclinations? Yet what is this Diffi- 
culty, compared with many others, that at the fame 
time prefent themfeives to our Mind ? This wonder- 
ful Reproduction of Parts, is it only a natural Con- 
fequence of the Laws of Motion? Or does it rather 
depend on a Chain of minute Buds or Shoots, a fort 
of little Embryos, already formed, and lodged where 
the Reproductions are to begin ? Are thefe Worms 
only mere Machines, or are they like more perfect 
Ani- 
