SOME PROBLEMS OF REPRODUCTION, 51 
vesicular nucleus, the germinal vesicle, with its chromatic 
elements concentrated and fused into a spheroidal mass, the 
germinal spot, supported by a delicate network of ‘‘ intra- 
nuclear protoplasm,” ‘‘nucleo-hyaloplasm,” or “linin.””? In 
the structure of its nucleus the ovum recalls the only other 
cells that enjoy a prolonged life uninterrupted by fission, and 
that attain to an equally large size—somatic ganglion-cells. 
The first symptom that marks the maturity of the ovarian 
ovum and its return to active life is the disappearance of its 
nuclear wall, and the merging of part of its ‘‘ achromatin” 
contents, together with the true nucleoli, in the cytoplasm ; 
while the chromatic elements of the germinal spot become 
separate as rods. It is to this process and stage that we must 
refer the elimination of mere trophic elements from the 
nucleus of the ovum—a process in many ways comparable to 
the disorganisation of the meganucleus of the conjugating 
Ciliates. There is every reason to believe that the nucleus of 
a cell destined to lie quietly feeding and fattening for days, 
months, years, or decades, must be of a very different character 
from one that has to undergo rapidly repeated fission ; in 
other words, between a purely anabolic and an essentially 
katabolic nucleus. If we accepted Geddes and Thomson’s 
view,! that there are actually entities that we can term 
anastates and katastates, we should have to reject their con- 
clusions, and say that this preliminary disorganisation of the 
germinal vesicle is the elimination of its anastates: for hence- 
forward all the phenomena manifested are katabolic, even 
without the advent of the male; and in ova which are not 
parthenogenetic the resumption of anaboly is henceforward 
impossible. This process is to some extent comparable 
with the elimination of the trophic element of the sper- 
matogonium, the blastophore, nucleated or non-nucleated ; 
but the parallel is a very remote one, and purely physiological. 
1 A view which I no more accept than I do Sachs’s view, that roots are 
formed at the base of a wallflower and flowers at the top by the migration 
downwards of “root-forming,” and upwards of ‘“flower-forming substances” 
(Wirzel und Blumen-bildende Stoffe). 
