1921] JEFFREY & TORREY—HERBACEOUS ANGIOSPERMS 31 
PLATE V- 
Fic. 27.—Part of t tion of infranodal region of stem of R. acris, 
mete bundles under slightly higher magnification than in previous two . 
figures 
Fr IG. 28.—Foliar trace of R. acris, somewhat more highly magnified to show 
absence of cambial activity. 
Fic. 29.—Leaf (left) and stem bundle (right) of R. acris, showing absence 
and presence of cambium. 
Fig. 30.—Leaf trace of R. acris, somewhat highly magnified to show absence 
of cambial activity. 
Fic. 31.—Stem and leaf bundles of R. acris, moderately magnified. 
Fra. 32.—Leaf trace of R. acris, somewhat highly magnified to show absence 
of cambium. 
PLATE VI 
Fic. 33.—Transverse section of old root of R. acris, showing absence of 
cambial gro 
Fic. 34.—Transverse section of stem of Sanicula, in region of branching 
node. 
Fic. 35.—Transverse section of same, slightly lower down in axis than in 
previous figure. 
Fic. 36.—One of amphivasal concentric strands occurring in nodal region 
of stem of Sanicula. 
1G. 37.—Transverse section in region of node of Rumex, showing presence 
of numerous series amphivasal strands, resulting from fusion of bundles 
in region of n 
Fic. 38. Sa of fig. 37, more highly magnified to show details of 
organization. 
PLATE VII 
. 39.—Transverse section through upper node of Zea, showing fusion 
of ua tia and bundles with corresponding structures in axis. 
Fic. 40.—Part of upper left hand portion of fig. 39, more highly magnified 
to show presence of amphivasal strands resulting from fusions in region of 
node. 
Fic. 41.—Foliar segment from lower woody region of axis of wax bean, 
showing absence of cambial activity in region of foliar trace. 
G. 42.—Transverse section through foliar segment of red clover, showing 
absence of cambial activity in foliar trace. 
IG. 43.—Transverse section through nodal region of Papaver sp., showing 
two leaf traces in center, in contrast to stem bundles, on either side, by absence 
of cambial activity. 
F —Transverse section of stem of Convolvulus sp., showing reduction 
1G. 44. 
of cambial activity in leaf segments as contrasted with those of stem. 
