16 



SEEDLINGS. 



[SECTION 3. 



to the large store of nutritive matter they contain, and this prevents their 

 d.-vrluping into actual leaves. Correspondingly, their caulicle does not 

 lengthen to elevate them above the surface of the soil ; the growth below 

 thccotylcdons is nearly all of root. It is the little plumule or bud between 



them which makes the upward growth, and which, being well fed by the 

 cotvlcdons, rapidly develops the next pair of leaves and raises them upon 

 ;i long iiiternode, and so on. The cotyledons all the while remain below, 

 in the husk of the fruit and seed, and perish when they have yielded up the 

 sture of food which they contained. 



23. So, even in plant* so much alike as Maples, there is considerable 

 difference in the amour-t of food stored up in the cotyledons by which the 

 is to be wade ; and there arc corresponding differences in the ger- 



1'ic. 1 <. One if the pair of keys or winged fruits of Red Maple; the seed-hear- 



ing portion cut open to show the seed. 15. Seed enlarged, and divided to show 



ninii'led embryo which tills it. Hi. Embryo taken out and partly opened. 



17. F.nili] yu whii-h lias unfolded in early stage of germination and begun to grow. 



18. Smiling willi next joint of stem and leaves apparent; and 19 with these parts 

 full-grown, and bnd at apex for further growth. 20. Seedling with another joint 

 of stem and pair of leaves. 



