No. I.] REGENERATIVE ENERGY. 39 
is capable of breaking up into parts without the concurrence of 
any visible changes in the nucleus. The enucleate individuals — 
if such they are entitled to be called — may agree perfectly with 
the nucleate individual in outward form and behavior. They 
live and grow, and coalesce not only with one another, but with 
the nucleate form. Whether they are capable of generating a 
nucleus or not was not ascertained. The multinucleate Actzn- 
ospherium breaks up in a similar manner without the inter- 
vention of the karyokinetic process; but here the individual 
parts generally contain one or more of the original nuclei. Two 
or more individuals may coalesce, but the coalescence extends 
only to the cytoplasm, the number of nuclei being the sum of 
those contained in the separate individuals before fusion. These 
remarkable facts appear to bear out Gruber’s conclusion: ‘‘ That 
the nucleus has no importance for those functions of the cell 
which do not stand in direct relation to reproduction ; such as 
locomotion (pseudopod-formation), inception of food, excretion 
(pulsation of contractile vacuoles), and growth. Even on the ex- 
ternal form it may be without influence” (No. 21, p. 66). Gruber 
(No. 19, p. 12) still maintains the accuracy of this view in every 
particular except that relating to the influence of the nucleus on 
the form of the cytoplasm. He now holds, in common with 
Weismann, Hertwig, Kolliker, Strasburger, and many other 
German biologists, that the form-creating and form-conserving 
principle is confined to the nucleus. How, when, or where the 
nucleus manifests its form-moulding power remains a mystery ; 
but that it gives the first impulse to the regenerative act must be 
inferred —so the argument runs— from the fact that the 
violent separation of nucleus and cytoplasm destroys the re- 
generative power in all cases, except where the process of 
reproduction is begun before separation is executed. This is 
the focal point of the question with which we set out. 
Aside from experiments in the artificial separation of nucleus 
and protoplasm, the principal arguments in support of this view 
are drawn from the phenomena of fecundation and cleavage, and 
are involved with certain theories of heredity which cannot be 
dealt with here. The observations of Gruber on Actiénophrys 
and Actinospherium, if the phenomena are not of a pathological 
nature, —and such an interpretation seems to be precluded, — 
should certainly make us hesitate to ascribe all the form-regu- 
