174 COLLEGE BOTANY 



Leaves with no Stomata on the Upper Surfaces. 



^ Stomata per sq. mm. on 



I^lant lower surface of 



leaves 



Olive (Olea europoea) 625 



Black walnut ( Juglana nigra) 461 



Norway maple (Acer pseudoplatanus ) 400 



Lilac ( Syringa vulgaris ) 330 



Red currant (Ribes aureum) 145 



Rubber plant (Ficus elastiea) , 145 



Nasturtium (Tropaeolum ma jus) 130 



Lily (Liliura bulbiferum) 62 



Leaves with few Stomata on the Upper Surfaces. 



Plant Lower Upper 



surface surface 



Bean (Phaseolus vulgaris) 281 40 



Poplar (Populus dilatata) 270 55 



Pumpkin (Cucurbita pepo) 269 28 



Tomato ( Lycoperslcum esculentum) .... 130 12 



Bitter sweet (Solanum dulcamara) 263 60 



Leaves with Stomata Nearly Equal on the Two Surfaces. 



Sunflower (Helianthus annuus) 325 175 



Cabbage (Brassica oleracea) 301 219 



Garden pea (Pisum sativum) 216 101 



Corn (Zeamais) 158 94 



( 23 25 



Oats (Avena sativa) s 07 40 



Leaves vyith More Stomata on Upper than on Lower Surfaces. 



Lower Upper 



surface surface 



Wheat (Triticum sativum) 14 33 



Water lily (Nymphaea alba) 460 



Water birch (Betula alba) 237 



Barberry (Berberis vulgaris) 229 



Cottonwood (Populus deltoides) 89 131 



Stomatal Movements. — The stomata, as previously stated, 

 open intO' tbe ii-regular intercellular spaces or chambers in the 

 mesophyll. Therefore, ■ many of the masophyil cells are brought 



