\ PHYSIOLOGY. | aot 
with some liquid. ‘The first is called the sacculus 
colliquamenti, and the liquor in it, the ammnios. ‘This 
vesicle grows larger, absorbs the chorion, which at 
last entirely disappears, and finally becomes the 
membrana interna of the seed, (§ 114). The amnios 
grows hard, and forms the cotyledons, (§ 114). 
As‘soon as the vesicle shews itself, the embryo of 
the future plant likewise appears gradually, which 
is, properly speaking, the corcle, (/. c.). | It is 
formed gradually, and becomes visible, in the sun- 
flower, (Helianthus annuus), three days after im- 
preenation; in the cucumber, (Cucumis sativus), 
a week after; and in Colchicum autumnale, some 
months after. It is soft in the beginning, but in 
time becomes, like the vesicle which contains it, of 
a better size and firmness. The vesicle does not 
in all seeds increase in the same form, in.some It 
grows larger in its whole circumference, in others 
it grows longer towards one extremity, and the sides 
aiterwards become extended. 
§ 296. 
Thus the seed comes to maturity, and when per- 
fectly ripe, separates in different ways from its mos 
ther plant, and begins a new life itself, passing 
through all the scenes again, just now explained, 
‘This is the common way in which plants are pro- 
gagated. But we have plants, which do it in another 
way besides evolving their seeds. At the stem, or 
near the angles of the leaves, nature or even acci- 
dents form sometimes knots, which become buds, 
and separating spontaneously from the plant itself, 
A send 
