KEIMBAHN-DETERMINANTS 241 
germ cells and their reappearance in the odcytes or 
mature eggs can only be conjectured. They seem to 
disintegrate into very fine particles which become 
thoroughly scattered within the cell body and mixed 
with the cytoplasm. It has been suggested (p. 68) 
that they may retain their physiological characteris- 
tics and become concentrated again in the growing 
odcytes into morphologically similar bodies, in- 
creasing in the meantime, by multiplication or in 
some other way, until they equal in mass those of 
the preceding generation of germ cells. On the other 
hand, they may all, like the ectosomes of copepods, 
be temporary structures produced at a certain time 
and place under similar metabolic conditions, and, 
becoming associated with particular parts of the 
cell contents, thus be constant in their distribution. 
Several ideas have been advanced regarding the 
fate of the eliminated chromatin in Ascaris. The 
ends of the chromosomes which are cast out into the 
cytoplasm are not equally distributed among the 
daughter cells nor does there appear to be any mech- 
anism for their definite unequal division. These 
facts argue against the theory that these cast-out 
chromatin bodies serve as determinants and also 
make improbable the hypothesis that they enable 
the somatic cells to differentiate, whereas the germ 
cells which do not undergo the diminution process 
remain in an indifferent condition, since their cyto- 
plasm lacks this material (Montgomery, 1911, p. 792). 
However, the fact that during the early cleavage 
divisions in some animals (see p. 218) large amounts 
R 
