51 
haricot bean than for the castor-oil plant. But the sum obtained in 
experiment No. 2 was very much below that stated in experiment 
No. 5. The duration of this experiment and its prolongation until 
the approach of the vegetating period appears to me to account for 
this difference. This hypothesis 1s supported by the results of experi- 
ments Nos. 1 and 4, the first having lasted six days and the other less 
than four. 
(5) By eomparing the ratio oa for similar experiments made in 
the light and in the dark, we see that there is always a difference of a 
quarter of the value of this ratio in favor of the dark; or, in other 
words, a seed placed in the dark always exhales more carbonic acid 
for the same quantity of oxygen absorbed than a seed kept in the 
light, even although sometimes, as we showed in experiment No. 3, the 
absolute quantity of carbonic acid exhaled is less in the light than it is 
in the dark. Finally, while in the light the carbonic acid released 
is always much less in quantity than the oxygen absorbed, the con- 
trary may be the case in the dark, where the absolute amount of car- 
bonic acid may even exceed the absolute quantity of oxygen, as is 
proved in experiment No. 4, where the absorption of oxygen 37.36 
corresponds to an exhalation of 42.54 of carbonic acid. 
(6) In order to consider the influence exerted upon the ratio 0? by 
the nature of the grain itself under different conditions as to light 
and darkness, it is only necessary to consult the conclusions which 
precede, and note the marked differences that distinguish the albumi- 
nous and oily seed of the castor oil from the nonalbuminous and 
starchy haricot bean. 
(7) The facts which precede complete the explanation already 
given of the transformation of legumin into asparagin under the 
influence of light. In general, the absorption of a greater quantity 
of oxygen only assures the formation of asparagin in so far as the 
amount of carbonic acid exhaled is less than the amount of oxygen 
absorbed; since asparagin is poorer in carbonic acid and richer in 
oxygen than legumin, all the conditions favorable to that formation 
are to be found demonstrated in the results of experiment No. 4, with 
seeds exposed to the light. It is very probable that a portion of the 
oxygen which had disappeared and that was not found as carbonic 
acid was absorbed by the albuminoids when forming asparagin, and 
we know from other sources that this substance seems to form in the 
majority of seeds during the process of germination. 
This absorption of oxygen during the period of germination is 
still greater in the castor-oil seed than in that of the bean. The oily 
seed, therefore, seems to be more favored by nature from a physio- 
logical point of view. 
1 
i . CO, : 
(8) We might be tempted to compare the ratio om obtained during 
the time of germination, with the same ratio during the period of 
vegetation. But the sum for the vegetating epoch has only been 
precisely fixed in the dark, which for green plants is entirely an ab- 
normal state. As, on the other hand, it is impossible to gauge exactly 
