499 
Respiratory Activity of the Gynaeceum. 
specimens of the same pair by 0*05. The respiratory quotient in both kinds 
of material was somewhere below unity, except in Pelargonium zonale , in 
the pollinated gynaeceums of which it rose above unity, its maximum being 
i- 2 , while in the unpollinated gynaeceums it fell well below unity. 
Slight environmental changes, such as temperature and moisture in 
the atmosphere, or changes in the material itself, such, for instance, as 
would probably occur owing to the length of time which elapsed between 
the cutting of the flower and experimenting upon it, appeared to affect the 
oxygen absorption in a more marked degree than the amount of carbon- 
dioxide evolved by the material. 
The net result of the whole work is to show that pollination not only 
produces a rapid rise of the respiratory activity, but also affects the 
respiratory quotient of the gynaeceum. 
The foregoing work was carried out in the Botanical Laboratory at 
the Melbourne University. I wish to record my indebtedness to Professor 
Ewart for the interest he has taken, and for the advice he has given me. 
