MR. A. J. EWART ON ASSIMILATORY INHIBITION. 
393 
III. Buzus sempervirens var. arborescens.—Specimens taken after 
similar exposure showed at first no assimilation, but after 3 
hours at 15? C. weak and in 1 day fairly active from all parts 
: with normal chlorophyll grains. 
_ 8 grammes green leaves. | 8 grammes living but browned leaves. 
(Twigs=1:7 grms.) | (Twigs=1:3 grms.) 
Reading. Time. ver ; volved Reading. Time, M" } volved 
1800 ec. |11 Aat | 181 ee |ll am. 
178:5 ec. | 11.80 ,, l5 ce.) 179:5 c.c. |11.30 ,, L5 eec.) 
1778 de. |12 , |07 ce | ¥ 1788 c.c. 12  , | 07 ee. | š 
176-0 e.c. | 230 r.m. | 033 ec. } E | 178 ce. | 250 r.m. | 0:16 c.c. E 
1754 ce. | 3 , |06 ce | E. li73ec.|3 , |06 cals 
1746 oc. | 3.30 ,, 08 cec.) 176:7 ec. | 830 ,, 06 cc. 
17391 c.c. | 430 ,, 07/5 c.c. Light. | 1755 c.c. | 430 ,, 06 cc. Light 
[172566 | 5 4 |06 co. 1747 ce. | 5 n |08 ce, 
171:8 c.c. | 5.30 ,, 07 ec| . | 1738 c.c. | 530 ,, 09 cc} | 
f Next day. 1 š | Next day. 1 š 
1585 e.c. | 9.30 Aa. | 0°83 c.c. | "E 159-1 ec. | 9.30 a.m. | 0:92 c.c. | É 
| 3rd day. R | 3rd day. e 
1577 «e. 10.30 Aa. | 0-4 ee. | 1582 ee. 10.30 a. | 0:45 c.c. 
In the case of Buzus it is possible that the large amount of 
CO, which the frozen leaves at first evolve when thawed is partly 
due to the setting free of pre-formed CO,, retained mechanically 
by the frozen tissue. Hence the subsequent fall followed by a 
secondary rise to the true respiratory maximum. 
Without attaching too much importance to the results thus 
obtained, still it appears that (1) respiration may be active 
whilst assimilation is still absent, and (2) respiration recovers 
from exposure to a low temperature more rapidly and responds 
more readily to an increase of temperature than assimilation 
does. 
In certain cases preparations which at 1? C. show a weak 
evolution of oxygen, when brought to a temperature of from 
15? C. to 20? C. cease in a few minutes to evolve oxygen, after a 
short interval, which may be as long as an hour, recommencing to 
evolve oxygen with normal rapidity. This stoppage does not 
appear to be due, as at first seems to be the case, to the effect of 
