122 
Journal of Agricultural Research 
Vol. XXIII, No a 
The very low respiratory quotient at o° C. is particularly interesting 
because it suggests storage of oxygen at low temperatures as at least one 
cause of the favorable effect of low temperatures upon after-ripening. 
Even at 19 0 , the weight of oxygen taken in was greater than that of C 0 3 
given off, so that unless some of the excess oxygen was split off as water, 
the seeds were actually gaining in dry weight. The obvious suggestion 
here is that oxygen is being used in the transformation of fats to sugars 
or in the formation of organic acids. Sugars and acids have been 
shown by Applemann (r), Atwood (2), Brannon (5), Eckerson (7), and 
Jones ( 14 ) to accumulate during storage of dormant structures at low 
temperatures. Eckerson (7), in fact, showed an increase in acidity of 
haw and apple seeds during incubation at low temperatures, which were 
favorable for after-ripening. I have found that the after-ripening of 
apple seeds takes place also in commercial cold storage when the seeds 
remain within the intact fruit. While perhaps it should not be expected 
in this case that oxygen would be available for storage in the seeds, still 
the volume of the respiratory exchanges of the seeds within the fruit 
must be small and must be governed more or less by the respiratory 
activity of the surrounding pulp, so that the maintenance of a low respir¬ 
atory quotient, with concurrent increase in the acidity of the seeds, may 
not be out of the question even here. 
Possibly also the increase of oxidizing enzyms during after-ripening at 
low temperatures, as shown by Eckerson for apple seeds, and by Crocker 
and Harrington (6), Jones ( 14 ), and Rose (21) for other seeds, and the 
fact that their catalase activity at least is exceedingly high immediately 
after germination, as I have found in work as yet unpublished, and as 
previously reported by Crocker and Harrington (6) and by Jones (14) for 
other seeds, are significantly related to their respiratory exchanges, 
especially to storage of oxygen and low respiratory quotient during after- 
ripening at low temperatures and to intense oxidation with high respira¬ 
tory quotient in the first stages of germination. The correspondence 
between respiratory activity and catalase activity is especially interesting 
in view of previous work by Applemann (r), Crocker and Harrington (6), 
and Kohl ( 1 5) which seems to connect this enzym definitely with respira¬ 
tory processes. 
In the last two periods of the experiment, the naked embryos were used. 
Germination began at once, and in less than three days all had germi¬ 
nated There was the customary tremendous increase in respiratory 
intensity. There was also a slight increase in the respiratory quotients 
above those which were normal for the dormant seeds at the temperatures 
used, indicating that, in this early stage of germination, oxygen-rich sub¬ 
stances were being respired more rapidly than the fats were being broken 
down to their component sugars. During the last period the oxygen in 
the respiration apparatuses, as computed from their known volume, was 
quantitatively used up, and the respiratory quotients were probably 
somewhat higher than they would otherwise have been. 
The temperature coefficients for oxygen consumption and for C 0 3 pro¬ 
duction in consecutive periods of the preceeding experiment are given 
in Table III. 
Table III shows values for Q 10 ranging from scarcely more than 1 to 
nearly 4, with two exceptional higher values for C 0 2 production at low 
temperatures in case of lot A. The values are greater for lot A than for 
lot B, emphasizing again the difference in response of the two lots to 
