94 
BOTANICAL GAZETTE [FEBRUARY 
results were also obtained with the recorder (see fig. 12), but it 
will be convenient to preface them by the simpler experiments 
in which the condition of the soil is not taken into account. 
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Fic; 7; 
EXPERIMENT 23, fig.7. March 10, 1899. CAMPANULA, 
: Io Zero line drawn. 
:58 Attached leaf on bulb R, Cut leaf (stomata shut) on bulb B. 
:58-11:46 Temperature of attached leaf on R sinksas stomata open more 
widely. 
147 Plant moved from damp greenhouse (T. 19°, Psy. 78%) to dry 
ie. greenhouse (T. 21.2°, Psy. 52.8). 
:47-12:18 Temperature of R rises (closure of stomata). 
18 Plant moved to damp house (T. 19.6°, Psy. 812). 
:18-12:38 Temperature of R sinks as stomata open. 
£45 Plant moved to dry house (T, 22.9°, Psy. 51.5%). 
718 The temperature reading practically the same as the zero line 
at 9:58 (Z¢., before the leaves were placed on the bulbs). 
This is also true at 12:18; the inference being that in the 
dry air the stomata closed so completely that the tempera- 
ture of the attached leaf (R) was the same as that of thecut 
and withered leaf (B), 
