Growth of Amputated Parts and Grafts 117 
besides the fin margin, the notochord and the spinal cord 
take part in this new formation. It is interesting that 
the tail of a tadpole is capable of such a regenerative 
new formation not only in the caudal direction but also 
in the opposite direction.” 7° 
We say then that these phenomena, which the ampu- 
tated tail of the tadpole presents, can be cited by the pre- 
formationists against the epigenesists, as well as by the 
latter against the former. For the former can object 
that the progress of the histological differentiation in 
the fragment of tail cut off from all the rest of the 
organism would denote the absence of any action of 
the organism upon the development of this part of the 
body, and the epigenesists on their side could show that 
the power of the tail to regenerate even in the direction 
from the tail toward the head, could not be explained 
by preformation, even with the aid of reserve idioplasm, 
for that could effect regeneration only in the direction 
from the head toward the tail. 
It is the same with Born’s celebrated experiments on 
the grafting of certain fragments of tadpoles upon one 
another or upon complete tadpoles, which are opposed 
to simple epigenesis and at the same time indicate a 
process of epigenetic nature. 
In the first place they are opposed to epigenesis. For 
in all grafts of parts of tadpoles upon complete tadpoles, 
the grafted parts have continued their development regu- 
larly as if they had remained united to their own 
organisms. Therefore the rest of this organism has not 
under normal conditions any influence upon the 
development of these portions. 
Born: Uber Verwachsungsversuche mit Amphibienlarven. 
Leipzig, Engelmann, 1897. P. 32—33. 
