19 1 2] 



STARR— ANATOMY OF DUNE PLANTS 



283 



TILIA AMERICANA 



Leaf ~ 



M 

 T 90 m (90-108) 



Stem 



x 



M 



X 



UE. 

 P... 



138^(135-156) 



17 



26 



19 per cent 

 29 



23 



17 percent 



Sp.. . . 36 =46 

 LE . . . 11 = 

 OW... 3.7 



45 = 33 

 52 =38 



12 



17 



12 



Cu. . . 



4 4 



I -S 



N. 

 D. 



W 

 F. 



L.. 



R. 



C. 



59 



38 m(53> 



2-7 

 2.8 



9.6 



2-5 

 58 



63 



41 

 2.8 



2.4 

 9.1 



i-5 



5° 



^(41) 



A".— Cells of upper epidermis smaller In both bands of sclerenchyma in the 



in depth, larger in surface, sometimes phloem and collenchyma under the 

 divided periclinally ; side walls on lower cork, slightly less in X; little variation 

 surface wavy, upper and both in M in walls and lumina of the fibers, but 

 plane; deeper palisade and tendency vessels more numerous and larger in X. 

 toward second layer; midrib as in preced- 

 ing X. In both hairs in the axils of the 

 veins; cuticle ridged.— Figs. 16 and 17. 



16 



17 



tigs. 16 and 17. — Tilia americana: sections of leaves; fig. 16, mesophytic form; 

 fi g- 17, dune form. 



