00 



SEEDS .dyi> SEEDLiyGS 



11. Germinationof the Morn- 

 ing Glory. At the 

 left, the seedling as it 

 appears Avlien hreal^ing 

 from tlie soil : at the 

 right, the same seedliD,Lr 

 a little later, the seed 

 coats thrown otT, the 

 stem straightened, and 

 the cotyledons opened. 



variety of methods. When the culj-hnhjiis are tlesigned 

 to act in the sunlight as green i'oUage for a time, tliey are, 

 in general, brought out of the 

 ground by the lengthening of the 

 cauliele. As it grow.s, tliis usually 

 bends abruptly just belo^v tlie 

 cotyledons; and the top of the 

 loop thus formed is seen -when 

 the craeking of the soil allows 

 one the first sight of the springing 

 seedling. The extraction of the 

 leafy parts is thus managed ^vith 

 the least danger of injury from 

 the resistance of the soil (Fig. 11), 

 and at the same time the seed 

 coats are often slipped off. 



25. Tlie main part of the origi- 

 nal seed ma,y remain permanently 

 buried, ^^'hile tlie luitrient con- 

 tents are gradually absorl>ed and carried away to the 

 actively growing regions of tlie root and the ascending 

 shoot. This is the case in the Horse-chestnut. The coty- 

 ledons are mere reservoirs of food. 

 Their stalks elongate (see Fig. 12), 

 freeing the cauliele and plumule 

 from the sliell. The root develops 

 strongly, and the plumule rises, 

 looped, toward the surface. 



26. The end of the root for a 

 greater or less length, according to 

 the size of the plant, is always elon- 

 gating in growth, and slipping forward 

 between the particles of soil, which it 

 avoids or pushes aside as the occasion 

 demands. A portion just behind this smooth thrusting 

 tip, having become fixed in position, throws out a velvety 

 coating of so-called root Jiaira. These penetrate sidewise 

 into the minutest interspaces of the soil, and adlicre to 



Germination of Iho 

 Horse-chestnut. 



