546 FOLIAGE-LEAVES AND THE CHLOROPHYLL FUNCTION. 
EXPLANATION OF PLATE XIX. 
Arisema triphyllum.—Fig. 1. Specimen grown in open air. Fig, 2. Specimen 
with aerial members grown in an atmosphere devoid of CO,. 
Fig. 3. Specimen grown in darkness. Fig. 4. Specimen from which 
one leaf and the flower-scape were removed, grown in an atmo- 
sphere devoid of CO,. 
Fig. 5. Specimens of Zea Mays grown in an atmosphere devoid of CO,. 
Fig. 6. Normal specimens of Zea Mays. 
(The specimens of Zea were photographed in an inverted position.) 
