1918] LANGDON—RAY SYSTEM OF QUERCUS 319 
Lar 
Fics. 11~16.—Transverse sections: fig. 11, nodal section of 5 year old twig from 
lower part of tree I, showing well developed broad rays; g, leaf gap; ¢, leaf trace; 
hgs. 12, 13, int dal secti f shoots from central (12) and top (13) regions of tree I; 
©, compound rays; fig. 14, section of 10 year old wood from tree III; fig. 15, section 
of vigorous 14 year old branch from central region of tree I; broad rays broken upon 
entering cortical region into wedge-shaped masses of ray parenchyma (pf); fig. 16 
ee of suppressed 19 year old branch from tree III; figs. 11-14, X5.5; figs. 15, 16, 
44. 
