96 A TEXT-BOOK OF BOTANY 
posed that all of the details of germination given for the 
garden bean are found in the germination of all seeds. The 
conditions for germination, and such life processes as res- 
piration, digestion, etc., belong to the germination of all 
seeds; but the relations of parts to one another and the 
details of the es- 
cape of the young 
plantlet vary wide- 
ly, and should be 
examined in as 
many plants as 
possible. For ex- 
ample, in the scar- 
let-runner bean the 
cotyledons are not 
usually freed from 
the testa, the first 
internode of the 
stem developing 
the arch and free- 
ing the leaves, as 
may be seen in the 
serles shown in 
Figs. 89 and 89a 
which is completed 
by Fig. 57. 
Fic. 91.—Seedling of corn at several stages, showing Seeds such as 
the superficial position of the embryo, the unfold- 
ing leaves, and the roots; the single cotyledon is peas, castor-bean, 
not seen, remaining in close contact with the endo- squash, and corn 
sperm. 
also should be ger- 
minated, as they show important variations. For exam- 
ple, in the pea and the acorn the cotyledons, so gorged 
with food as to have lost all power of acting as leaves, 
are never extricated from the testa; but the plumule is 
pushed out by the elongation of the cotyledons at their 
