THE ROOT 



43 



become firmly glued to the surface. Firm support is thus 

 p afforded to the ascending creeper. 



64. Roots used for storage. — The roots 

 of almost all plants that 

 persist for more than a 

 single season serve, in 

 common with the stem, 

 as organs of storage, to 

 some extent. But their 

 forms are not altered 

 for the special purpose 



section through 

 Dodder and host 

 plant at the 

 point where the 

 haustorium, or 

 sucker, of the 

 former pene- 

 trates the bark 

 of the host ; p, 

 stem of the para- 

 site ; s, sucker, 

 piercing to the 

 wood of the host, 

 h (mucli magni- 

 fied) . — Sachs. 



34. 



Roots of Trum- 

 pet Creeper, 

 used in climb- 

 ing. 



35. Thickened storage roots in 

 cultivated plants. On the 

 left Carrot, on the right 

 Radish. In bt)th cases the 

 rootiscoufluent above with 

 an exceedingly shortened 

 stem bearing the leaves. 



of storage in ordinary cases. Yet roots are sometimes 

 much enlarged to hold the nourishment made by the 

 plant during one growing season for its use in the next. 

 Among the plants that owe tlieir early appearance in the 

 spring to food stored up in a somewhat fleshy root is the 

 Dandelion (Fig. 42). In certain plants the tendency to a 

 thickening of the root has been fostered by cultivation 

 and selection until from the original wild stock, not more 

 promising in the beginning than some of our common 

 herbs, such useful food plants as the Beet, Turnip, Parsnip, 

 and Radish have been produced. These make use of 



