22 
members, leaves, which usually differ considerably from it. 
bo” ao 
| B 
| 
| 
i 
| 
Sel, = ] 
== | 
= Gk 
Bele. Ip 
eles SOW Dawes 
Sf 
W 
x 
FIG. 4.—-Diagrammatic Longitudinal Section through a 
Young Maize Plant (Zea mais) [from Sachs]. W. pri- 
mary Toot ; o,i', 6”, &’”. adventitious roots spring- 
ing endogenously from the stem (s); 0, b’, b”. older j 
leaves, cut off short; b’”. young leaves of the terminal 
bud ; k, k. axillary buds. The growing points are 
represented black, the elongating parts grey; the ; 
parts left white are fully grown. The white tips of 
the root are root-caps. 
THE FLOWERING PLANT. 
This, 
among other points, dis- 
tinguishes the stem from 
the root. We have also 
seen that stems often 
bear adventitious roots 
(fig. 4), but this is not of 
primary importance, at 
least from a morphologi- 
cal point of view. 
Stem and leaf are so 
constantly associated that 
it is impossible to treat 
of one without reference 
tothe other. A collective 
name, that of shoot, has 
therefore been given to 
the stem with its leaves. 
The broadest grouping 
that can be made of plant 
members divides them 
into only two sets, viz., 
roots and shoots. 
The regions of the stem 
to which leaves are at- 
tached receive the name 
of nodes, while the in- 
tervening portions are 
known as_ inter-nodes. 
Nodes are often thick- 
ened, and adventitious 
roots generally arise from 
them. Where a leaf joms 
the stem there is an upper 
angle formed (usually 
acute), and a lower angle 
(usually obtuse). The 
former is known as the 
axil of the leaf. This 
point is mentioned here 
because it is the rule 
in flowering plants for 
branch stems to arise 
in leaf-axils (figs. 2, 4, 
and 35). Such branches, 
