l']^i- on wormi. 139 



ther this took place when the head was cut at dif- 

 ferent distances, and whether any difference, in the 

 method of dividing, would prevent the usual repro- 

 duction. It was, therefore, necefsary to observe, 

 whether the regenerative power existed in the whole 

 length of the worm, so that the head, however long 

 or fhort, would be equally fit to reproduce a tail. I 

 found that nature has limits, beyond which this re- 

 production of the tail can be no longer effected." 



The Abbe made many other inquiries concerning 

 this power of reproduction, but the next, which he 

 mentions to my purpose, was, whether the posterior 

 part or the tail, could produce a nev»r head. " I found," 

 says he, " that upon cutting off a certain number of 

 rings from the anterior part, the reproduction of the 

 head took place in every species of earth-worms 

 known to me ; and I did not fail to attend in a great 

 measure to the same things I had noted in the repro- 

 duction of the tail. If the number of rings taken off 

 be such that the quantity of the anterior part sepa- 

 rated be considerable, the reproduction of the head 

 will not take place till after a long time, and then 

 with difficulty ; and not in every species of those in-' 

 sects. But as reproduction is only delayed, not pre- 

 vented, by this kind of section, it may be concluded 

 that earth-worms, or at least some species of them, 

 reproduce not only the tail, but the head. When- 

 the rings cut off near the head are but fev/, the part- 

 reproduced is always equal to thit which was taken 

 off; but when there. are many, the new head ii com- 

 monly fliorter, and has fewer rings than the first.'" 

 He found, likewise, that the reproduction of a smalli 



