Zea mays

3.66 3.6/
3.68
3.66 TS of the wood of the primitive dicotyledon Orimys
winteri. This does not contain vessels and the tracheids (1)
are of rather uniform diameter. Both uniseriate (2) and
multiseriate rays (3) are present. (LM x 90.)
1 Tracheids
2 Uniseriate ray
3 Multiseriate ray
3.68 TS of the diffuse porous wood of the dicotyledon
Magnolia grandif/ora. The small and fairly uniform vessels
occur evenly throughout the growth ring except for a
narrow band of late wood (1). Numerous, narrow
multiseriate rays are presenr (2). (LM x 25.)
t Late wood vessels
2 Multiseriate rays
3.69 Trunk of a large specimen of Cedrus deodora
(cedar) showing the scar of a large side branch. In
gymnosperms (in contrast to most angiosperms, cf., 3.37)
the reaction (compression) wood, forming the thicker part
of the eccentric xylem, lies on the underside of the branch
(I, indiC:lIes the position originally occupied by the pith).
Note the callusing at the margins of the sca'r which is
beginning to cover the wound with (;Ork (2)
3.67 TS of the ring porous wood of the dicotyledon
Quercus alba (oak). The largc-diametered early-wood
vessels (1) contrast with the smaller-diametered vessels of
the late wood. The latter are distributed in more·or-Iess
radial bands of vessels (2) alternating with areas of very
narrow tracheary elements. Numerous rays are also
evident. (LM x 25.)
1 Early-wood vessels
2 Late wood vessels
I Onginal position of pith
2 Wound cork
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3.65