RELATION OF LEAF STRUCTURE TO PHYSICAL FACTORS 59 



50-70%; temperature 5O-75 : diphotophyll 250/1; epidermis, 

 upper 25 /4, lower 20/4; cuticle 2/4; chlorenchym (205 /*) i lacunose 

 row prolate palisade cells 60 //,; lacunose oblate sponge cells. (Plate 

 VII, fig. 2 a.) 



BIRCH THICKET : light 0.03 ; available water 18% ; humidity 40- 

 70%; temperature 48-72 : diphotophyll 175/4; epidermis, upper 

 20/4, flattened, lower 15/1; cuticle thin; chlorenchym (140/4) I 

 lacunose row prolate palisade cells 50/4; lacunose oblate sponge 

 cells. 



Brook bank . . . C. 205 /* P. I row, 60 A* S. 145 A* 



Thicket C. 140 A* P. I row, 50 M S. 90 A* 



65 ft ion (17%) 55 A (38%) 



Light 1/33; water 2%; humidity (0-10%) ; temperature 



-(2-3). 



ALPINE MEADOW : light I ; available water 12-17% > humidity 40- 

 55% ; temperature 4O -6"5 : diphotophyll 250/4; cuticle, upper 4/4, 

 lower 2/4; chlorenchym (205/4) I close row prolate palisade cells 

 70/4; loose oblate sponge cells. (Plate VII, fig. 2 &.) 



Brook bank . . . C. 205 A* P. i row, 60 M S. 145 A* 



Meadow C. 205 A* P. i row, 70 A* S. 135 A* 



O + IOA* (17%) IDA* (7%) 



Light i; water (3-8%) ; humidity (10-15%) ; temperature 

 10. 



GRAVELLY BROOK BANK : light i ; available water 8% ; temperature 

 55-76 : diphotophyll 250/4; chlorenchym (205/4) I loose row pro- 

 late palisade cells 60 /4 ; close oblate sponge cells. 



Brook bank C. 205 A* P. i row, 60 A* S. 145 A* 



Gravel C. 205 A* P. i row, 60 A* S. 145 A* 



o o o 



Light i; water (7-17%) ; humidity the same; temperature 



+ (i-5). 



Aconitum columbianum 



SUNNY BROOK BANK: light i ; available water 15-25% ; humidity 

 50-70% ; temperature 5O-75 : diphotophyll 300/4; epidermis 25/4; 

 cuticle 2/4; chlorenchym (250/4) i close row prolate palisade cells 

 75 /u, (one-fourth to one-fifth prolobate) ; lacunose irregular elon- 

 gated sponge cells. (Plate VII, fig. 3 a.) 



