262 RECENT CYTOLOGY 
differs from all other mitoses in the fact that in it an 
actual separation of whole chromosomes takes place ; 
it is a qualitative and not only a quantitative division. 
It is to this mitosis that the term reducing division is 
properly applied. 
We have to notice that at one stage of the process 
now described the chromosomes derived from the two 
parents are in a close state of fusion. It would seem 
as if the actual conjugation of chromosomes, which 
failed to take place when the conjugating gametes and 
their nuclei fused together in the formation of the 
zygote, was only delayed, and now occurs hundreds or 
Se... 
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thousands of cell generations after the actual process 
of fertilization, and immediatély before the production 
of those cells which are to give rise to the new 
individual. 
It may be pointed out that, although the chromo- 
somes which emerge from this fusion seem to be 
identical with those which entered into it, yet it is 
difficult to believe that they have not undergone some 
change, or exercised some mutual influence upon one 
another. If no such influence has been exerted, it is 
difficult to imagine any possible reason for the process 
of fusion taking place at all. 
In the higher plants a similar reducing division 
FIG. 43. 
