116 



THE SECOND BOOK OF BOTANY. 



usually obvious enough, and the micropyle may be 

 easily found. You have only to soak the seed till its 

 coats are distended with water, and, on squeezing, 

 the micropyle, or orifice in the coats, is made appar- 

 ent by the escape of water at that point. The place 

 of the micropyle is important, because the radicle of 

 the embryo always points toward it, and, in sprout- 

 ing, issues through it, and the relation of the micro- 

 pyle to the hilum determines the attitude of the em- 

 bryo. Seeds are straight, half inverted, inverted, 

 and curved, the same as ovules, and the same terms 

 are used to express these facts in regard to them. In 

 a straight or orthotropous seed (Fig. 249), the micro- 

 pyle being at the apex, you find an inverted embryo, 

 like Fig. 250. In this case the embryo is said to be 

 antitropal, or reversed. 



FIG. 249. 



FIG. 250. 



Micropyle. ; 



Hilum. 



If the micropyle be turned to one side, as in Fig. 

 251, an amphitropous seed, the embryo, will be ob- 



FIG. 251. 



FIG. 252. 



FIG. 253. 



