GAGER: CRYPTOMERIC INHERITANCE IN ONAGRA 467 
became differentiated into two unlike portions. In the cells of 
one half, the pangens fundamental to the distinguishing characters 
of the narrow-leaved branch became active, and the pangens funda- 
mental to the distinguishing characters of the broad-leaved branch 
became latent or wanting. In the cells of the other half the re- 
verse conditions obtained. 
From the very nature of the hypothesis of intracellular pan- 
genesis, this is, of course, a very formal explanation. 
In chapter XIX of my memoir® on Effects of the Rays of 
Radium on Plants, I have suggested that the effects of the rays 
may be due to their influence, not directly on the living matter 
itself, but indirectly, on the enzymes or other non-living inclusions 
of the cells. This idea of the possible réle of enzymes in morpho- 
genic changes has been more elaborately worked out by Spillman,” 
who rejects the notion of a supermolecular, organic pangen in favor 
of, for example, an enzyme acting on some other chemical body, 
such as a chromogen. ‘All known Mendelian phenomena,” says 
Spillman,* “may be explained as due to differences in the chem- 
ical constitution of the chromosomes in different groups.” The 
failure of a character to appear is attributed to “the failure of a 
single chromosome to perform a particular function.” A practic- 
ally identical hypothesis was suggested independently by Holmes.” 
Additional evidence that enzymatic action may be involved 
in mutation is found in the inference, made by de Vries" (p. 264), 
that mutating seeds remain viable longer than non-mutating ones; 
for it is well known that profound enzymatic changes occur in the 
aging of dry, resting seeds. Albo’s'* investigations indicate that 
the energy for the changes undergone by such seeds is enzymatic 
in origin, and he states that he was able to demonstrate that 
diastatic activity was either diminished or entirely wanting in 
seeds that had lost their capacity to germinate. Dry seeds of 
many families, and able to germinate, were found by Brocq- 
Rousseu and Gain’ to contain a peroxydiastase, which the writers 
claim was never present in seeds that had lost the capacity to 
germinate. Miss White," however, reports tests on the resting 
seeds of cereals, showing the presence in them of diastatic, ereptic, 
and fibrin-digesting enzymes, still active after a period of over 
* Loc. cit, 246. 
