106 OBJECT LESSONS IN BOTANY. 
Spireea. If little tubers here and there are attached to the 
fibres, the root is tubercular, as in Squirrel-corn. 
Fig. 838. Fibro-tuberous root of Peony. 
Fig. 339, Fibro-tuberous root of Spirea filipundula, 
Fig. 840. Fibro-tuberous root ef Mourning Geranium. 
293. All these fleshy forms, whether tuberous or fibro-tu- 
- berous, are filled with starch, deposited there in store, for use 
in the future growth of the plant. Many other forms of roots 
are described in larger works. 
LESSON XXVIII. 
OF THE STEM OR ASCENDING AXIS. 
994. Tue stem tending upward in its growth is often called 
the ascending axis. It does not in all cases continue to arise 
223. What purpose do fleshy roots serve ? 
Less. XXVIII. What is the subject of this lesson? 
