370 BOTANICAL GAZETTE [OCTOBER 
a perceptible tendency to horizontal growth. Large numbers of 
small roots were growing from the base of the bulbs in approxi- 
mately horizontal directions. No photographs were taken of 
this experiment. 
Fic. 5.—Representative roots of Christmas pepper plants which received con- 
stant treatment of carbon dioxide. 
Experiment D 
Burpee’s stringless green pod bean (Phaseolus vulgaris) was 
grown from seed without and with the 2 carbon dioxide gas treat- 
ments. The plants were harvested just after blossoming ceased. 
Fig. 8 shows the plants growing in the best of each set of triplicate 
pots. The difference between the plants growing in the 3 pots is 
small. Fig. 9 shows the roots of the plants appearing in fig. 8. 
z 
