4 BOTANICAL GAZETTE [ony 
respirometer through the stopcock tube. The potassium hydroxide 
was allowed to flow down the sides of the respirometer, the hood 
of the seed holder preventing its coming into contact with the seeds. 
So far as possible, measurements were made and absorption carried 
out without removing the respirometer from the bath. A second 
reading of the manometer was taken after absorption of the carbon 
dioxide. Barometer readings were taken after closing the chamber 
at the beginning, and again before absorption of the carbon dioxide 
at the end of the experiment. From the calibration of the respi- 
rometer it was possible to calculate its volume at the beginning (cor- 
rected for the volume occupied by the seeds) and at the end, before 
and after carbon dioxide absorption, a correction for the volume 
of the absorbent added being applied in the latter case. All 
volumes were further corrected to absolute zero, and to 760 mm. 
pressure. The difference between the volumes at the end of the 
experiment before and after carbon dioxide absorption represents 
the volume of carbon dioxide eliminated by the seeds, while the 
difference between the volume at the beginning of the experiment 
and that after absorption represents the volume of oxygen taken 
up by the seeds. These relations are expressed by the following 
formulae, which were used for the calculation: 
et V,=volume of respirometer, 
V,=volume of imbibed seeds, 
V,=volume of absorbent (KOH) used, 
T,=initial absolute temperature, 
T,=final absolute temperature 
B,=initial barometric pressure, 
B,=final barometric pressure, 
m,=initial manometer reading, 
m,=final manometer reading. 
A: V,— Rx tas 
(V,-V)23x Be 
B: (V,—V.)BS xs 
760 — 
C: V.-V.-V 2B RE 
( aX ce 
