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CLASSIFICATION OF PLANTS. 211 
ature herself indicates to the observer the species and many of __ 
e genera, by the- features of resemblance with which she marks — 
Jussieu thought that the key to the 
ul method was there ; since, in comparing the character of one 
those families with the genera composing it, he would obtain a 
10owledge of the relation of one to the other; and in comparing 
any among them, he would see how the characters common to all 
ants of the same family varied one from the other; he would 
Us arrive at a true appreciation of the value of each character, 
id this value, once determined by means of groups so clearl 
gned by nature, could be applied in its turn to the deter- 
mation of others which were not so strongly impressed with the 
y Seal; others which were the unknown in the great problem. 
B slacted for this purpose seven families already universally 
cognised ; those, namely, known as the Graminacem, the Filiacese, 
Labiate, ha Composite, the Umbellifere, the Crucifere, and 
“It is iticcine’ that the embryo is identical in all plants of 
cal these families ; it is monocotyledonous in the Graminacez 
sMiacex, and dicotyledonous in the other five. The structure 
Seed is also identical, the monocotyledonous embryo being | 
| oe axis of a fleshy albumen in the Liliacez, and upon 
nous embryo is Basti at the summit of a hard vere 
bumen i 
a farinaceous perisperm in the Graminacee, while the 2 
