io4 



THE PHYSIOLOGY OF S'fOMATA. 



9 night 



3a.m. 6 9 12m. 3p.m. 6 



Fig. 33. — Daily periodicity in movements of stomata of Fouquieria splendens. Extreme sizes 

 plotted in thin lines; means in heavy line. July 10. 1904. 



Table 5i. — Stomatal movement, Fouquieria splendens, July 10, 1904. {Fig. 33.) 



Table 52. — Size of stomatal openings under normal conditions, material growing on Uni- 

 versity of Arizona campus, July 27-28, 1906. Well-watered plants of Fouquieria splen- 

 dens, in irrigated {Tourney) garden. {Figs. 34 to 37, inclusive.) 



Time. 



July 27. 



July 28. 



8 h 30 n 

 10 30 

 1 00 



3 20 



6 30 



8 30 



3 30 

 5 30 



7 45 



9 00 



a. m 



a. m 



p. m 



p. m 



p. m 



p. m 



early dawn 



a. m 



a. m 



a. m 



Primary leaves. 



Micra. 



3 to 9 



6 12 (!) 



4-5 12 

 < (4-5) 

 ( 6 to 9 



5 

 f (o) 



1 to 5 



i. (6) 

 3 to 8 



3 9 



4 10 



J 4 9\ 



\ 4 10. 1 



Secondary leaves. 



Upper. 



Micra. 

 5 to 6 

 4 9 

 3 7-5 



|(o) 



< 2 to 6 



o 3 



5 

 6 



7-5 



Lower. 



Micra. 

 2 to 6 



2 4-5 



3 7-5 



2 4-5 

 o 4 



3 

 6 



7-5 

 9 



Notes. 



Partly cloudy. 

 Cloudy. 

 Do. 



Partly cloudy. 



Clear. 

 Sunlight. 

 Do. 



Do. 



