Seeds and their Germination 



17 



is to be done down in the soil, and that of the stems up in the light ; so 

 the sooner they get into these positions the better. 



Fine white hairs may be seen on the root and its branches 

 to within a short distance from the tip. As the root pushes 



Fig. 



23. — Diagram for ends of 

 glass germinator. 



Fig. 24. — Seedlings 

 showing root hairs. 



on, the oldest ones are worn off, but new ones are constantly 

 formed towards the tip. They make their way in between the 

 fine particles of soil in search of water, and greatly increase 

 (from five to twelve times) the absorbing surface. 



Ex. 2. Fasten some seeds, which have germinated until the roots are 

 about an inch long, to strips of wood. Place them in an inverted flower- 

 pot, in which the water stands to a height of 2 inches. Let the roots 

 in one dip into the water ; place the second.lot higher, taking care that they 

 are some distance above > the water. After they have grown an inch or 

 two, note the absence of root hairs in the first lot. The drier the soil, the 

 more numerous are the root hairs. Some water plants, however, have 

 abundant root hairs. 



