244 SECRETS OF ANIMAL LIFE 
inheritance and some do not. Moreover, the 
Mendelian doctrine that all characters segregate in 
inheritance and are uninfluenced by crossing is far 
from being substantiated by Gates’ results. He 
finds Mendelian splitting, it is true, but much more 
besides. He finds illustrations of blending and 
hints of the mutual influence of hereditary char- 
acters; he finds curious results called “ mutation 
crosses”” and “twin hybrids,” which are anything 
but Mendelian. In short, the Mendelian categories 
are far too rigid, savoring too much of the in- 
animate domain. 
The step gained is the demonstration that the 
bodily peculiarities of mutants are correlated 
with visible disturbances in the germinal organiza- 
tion. The next step is to discover all we can in 
regard to these germinal disturbances. Dr. Gates 
has described changes in the number, shape, size, 
arrangement, and structure of the chromosomes; 
but he is careful to point out that we must push 
beyond these to chemical or functional changes 
in particular chromosomes or parts of chromosomes. 
Furthermore, changes may perhaps occur in the 
mysterious karyolymph or gel which forms the 
ground-work of the nucleus. But behind the 
question of the nature of the germinal changes 
looms the problem of their origin. The Proteus 
of the organism has changed into the Proteus of 
the chromosomes. Do these germinal disturbances 
come about in response to subtle environmental 
stimuli penetrating in from without, or does the 
