RELATION OF LEAF STRUCTURE TO PHYSICAL FACTORS 69 



BROOK BANK THICKET: light o.on ; available water 18-20% ; hu- 

 midity 60-85%; temperature 47 -69 : diphotophyll 90/4; cuticle 

 thin; chlorenchym (50/4) I row funnel palisade cells 35/4; oblate 

 sponge cells. (Plate VIII, fig. 2 b.) 



Gravel C. 125/1 P. 2 rows, 75/1* S. 50 /* 



Thicket C. 50 M P. I row, 35 M S. 15 n 



75 A* i row, 40/4 (53%) 35 M (70%) 



Light i/ioo; water -f 15%; humidity +(8-32%) ; temperature 



(I0-20). 



Bidens bigelovii 



FOOTHILL HALF GRAVEL: light i ; available water 4.5-7.5% ; hu- 

 midity 28-77%; temperature 57-89 : diphotophyll 225/1; epi- 

 dermis, upper 20-25 /A, lower, 15/^5 cuticle 2/*; chlorenchym 

 (185 (JL) i compact row prolate palisade cells 100/1,; compact glo- 

 bose sponge cells. (Plate VIII, fig. 30.) 



FOOTHILL THICKET: light 0.0166; humidity 38-80%; tempera- 

 ture 53-85 : diphotophyll 50/1; epidermis, upper IO/A, wavy, lower 

 5/u,; cuticle thin; chlorenchym (35 /A) i loose row funnel cells 15 ju,; 

 loose oblate sponge cells. (Plate VIII, fig. 3 &.) 



Half gravel .. C. 185 it P. i row, IOO/K S. 85 A 



Thicket C. 35 M P. I row, 15 V- S. 20 /* 



I50M 8SM (85%) 65M (76%) 



Light 1/60; water the same; humidity +(3-10%) ; temperature 

 4- 



Capnoides aureum 



GRAVEL: light i; available water 2.5-5.5%; humidity 30-65%; 

 temperature 55-76 : diphotophyll 200 /*; epidermis, upper 30 /A, 

 lower 25 /A ; cuticle thin ; chlorenchym ( 145 /A) I close row prolate 

 palisade cells 50 ju,; compact oblong sponge cells. 



SPRUCE: light 0.03; available water 12-16% ; humidity 40-70% ; 

 temperature 48-72 : diphotophyll ioo/*; epidermis 25/1; chlor- 

 enchym (SO/A) i row funnel palisade cells 30/4; loose oblate sponge 

 cells. 



Gravel C. 145 /* P. i row, 50 ft S. 90 /* 



Spruce C. 50 M P. I row, 30 At S. 20 /* 



95 /* 20A (40%) 70M (77%) 



Light 1/33; water -f 10% ; humidity +(5-10%); temperature 



