36 BORTHWICK—ADVENTITIOUS ROOTS. 
F1G. 34.—Twig kept horizantal. Adventitious roots have developed on 
lower side. 
F1G. 35.—Adventitious roots developed in 36 hours in warm, moist 
chamber. 
F1G. 36.—Coral-like mass of adventitious roots developed at base of long 
branch. 
G. 37-—Long branch with spur shoots, showing coral-like mass of 
adventitious roots at their bases 
Fic. 38.—Transverse section of adventitious root. 
PLATE XI. 
FIGS. 39-43-—Apple tree. 
FIGs. 39, 40, and 41.—Twig one of whose adventitious roots was caused 
0 grow into a glass tube filled with moist. sand. Fig. 39, before tube was 
aia Fig. 41, with tube attached. Fig. 4o, after tube was removed. 
FiG. 42.—Transverse section of stem showing beginning of adventitious 
root by dilation of medullary-ray. 
FIG. 43.—Section transverse to stem and longitudinal to adventitious root 
which has pierced the periderm. 
FIGs. 44-49.—Wych elm 
FIGs. 44 and 45. Shem showing numerous adventitious medullary-ray 
roots. 
Fics. 46-47.—Longitudinal sections of bud and root-rudiment from burr 
on which they were growing side by side. 
FIG. 48.—VPieces taken from burr showing elongated adventitious roots. 
Fic. 49.—Section radial longitudinal to stem and adventitious medullary- 
ray root. 
Fic. 50. i heey laurel branch with numerous adventitious roots. 
