v 
6 | ELEMENTARY: BOTANY 
(Latin scutwm, ashield) ; this answers in part to the cotyledon. 
The rest of the grain, chiefly yellow, is food material. 

Figs. 4 ro 7.— MAIZE. 
4. EXTERNAL VIEW OF GRAIN. 5.—EMBRYO, __.. 
6 aND 7.—Srepuines, Until. the plumule 
REMOVED FROM GRAIN. 
a, remains of style; y, stalk of attachment 
to cob; sc, scutellum ; p, plumule; 7, radicle ; 
sh, root-sheath ; rh, root-hairs ; ¢, food-material. 
lateral roots. 
_ Stages in The first 
Germination. step in 
- germination is in- 
variably the swelling 
of the seed owing 
to the taking in of 
water; then the skin 
bursts In consequence 
of the pressure of 
the radicle against 
it; this soon  pro- 
trudes, and the skin | 
goes on splitting 

‘The 
soon gives 
off branches forming 
also emerges. 
radicle 
In maize, two other roots, called secondary, 
arise from the scutellum. The first root has a little sheath at its 
base, so that it is possible to tell which the primary root is. 
The plumule grows into the shoot; in maize the leaves 
ensheathe the stem. 
COMPARISON OF SEED OF BEAN AND 
GRAIN OF MAIZE, 
BEAN. 
|. A seed. 
2. Brown skin is testa. 
3. Two fleshy cotyledons, 
containing food. 
4. Food stored within the 
young plant. | 
5. Radicle develops into 
primary root, bearing 
lateral branches. 
6. Plumule grows into shoot. 
MAIZE. 
A seed + seed-vessel. 
Skin is testa + wall of seed- 
vessel. 
One cotyledon. 
Food supply external to the 
young plant. 
Radicle develops into primary 
root with lateral branches ; 
in addition there are two 
other roots, which are 
soon as long as_ the 
primary root. 
Plumule grows into shoot. 
