28 THE VEGETABLE WORLD. 
ranean stems. The Solomon’s Seal (Fig. 29) presents a subterranean 
stem, thick, fleshy, whitish, and indented on its upper surface 
with scars corresponding with 
B the bases of old aerial stems 
& (thence the name of sea/ which 
this plant has preserved). This 
|: i, subterranean stem terminates at 
i hg its foremost extremity with a 
25D uf . leafy and flower-bearing ax!s, 
) placed behind a terminal bud, 
B)), which will develop itself the 
following year. Many plants, as 
the iris, flowering rush, water 
trefoil, and carex, alike present 
subterranean roots. Fig. 30 
represents the subterranean root 
of the [ris germanica. 
These roots have, received pes: 
4 GAY 'y | 
\ piiwma, a root or root stock. They 
“SV creep obliquely or horizontally 
} under the surface of the soil, and 
vegetate at their most advanced 
point, whilst the hinder part is 
gradually destroyed by age. This 
mode of existence in subterra- 
nean roots is well exemplified 
in Fig. 31, which represents the growth of a sprig of Carex, 80 
called from careo, “to want,” its upper spikes being seedless. In 
this engraving is shown the horizontal and creeping axis, which 
represents at once scales or modified leaves and root-fibres, and 
-which sends out leafy shoots at intervals. The shoot 1 is only 
one year old,—in the next spring it will assume the form of the 
shoot 2; the following year it will bear flowers and fruit, as in 
3; the production of fruit will mark the term of its existence, 
as shown in 4. Fig. 32 is the Maize plant (Zea Mays). ; 
Another very remarkable kind of subterranean root is that 
which forms the central or essential part of Julbous plants. ‘Cut 
“Ararg 
Fig. 28.—The Hop-plant. 
