474 



BOTANY. 



part such that the yeins rarely are parallel to each other, and 

 in their anastomosing they form an irregular net-work. 



The germination of Dicotyledons may be illustrated by a couple of 

 examples. In the seed of the Windsor Bean (Fig. 367) the embryo 

 entirely fills up the seed-cavity, the endosperm having all been ab- 



' ■"■ Fiaa. 367-8.— Gebmination op Dicotyledons. 



FiQ. 368. 



Fig. 367.— Hcia/o6a. .4, seed with one cotyledon removed; c, remaining cotyle- 

 don ; ifcw, the plumule ■ w, the radicle : s, seed-coat. B, germinating seed ; 8, seed- 

 coat, partly torn away at I; n, the hilum ; et, petiole of one of the cotyledons; *, 

 curved epicotyledonary stem ; he, short hypocotyledonary stem ; A, main root ; ws^ 

 its apex ; ftre, hud in the axil of one of the cotyledons.— After Sachs. 



Fig. WS&.—Rlcinus communis. /., lonp:itudinal section of the ripe seed. II., ger- 

 minating seed with the cotyledons still mside of the seed-coat (shown more distinct- 

 ly in A and B). «, seed-coat ; e, endospenn ; «, cotyledon ; he, hypocotyledonary 

 stem ; w, primary root ; w', branches of root ; x, caruncle, a peculiar appendage to- 

 the seeds of Euphorbiaeeae.—Attei Sachs. 



sorbed. The thick cotyledons lie face to face, and are attached belo'w 

 to the slnall stem of the embryo plant. The stem extends upward a 

 short distance between the cotyledons, bearing a few rudimentary 

 leaves and itself ending in » punctum vegetationis (Fig. 369, «s), the 

 whole constituting the plumule. The downward prolongation of tha 

 stem (commonly but erroneously called the radicle, for it is not a little 



