262 VEGETATIVE PROPAGATION 



" eyes " in the tubers are really buds. When used for propagation, 

 the potato is cut so that each section has at least one " eye." 

 These sections can be planted and each bud or "eye " will develop a 



root system and an aerial 

 stem. Each tuber can 

 form as many plants as 

 it has buds or " eyes." 

 Nourishment in the form 

 JOT&JV of starch is stored in the 



tuber and feeds the grow- 

 ing plant until its leaves 



A whole bulb and the cut section of two bulbs are i j 



shown. Note the short stem and the thick fleshy leaves are priClUCea. 



arranged around the stem. timeg when potatoes are 



kept in a damp cellar, the eyes absorb moisture and begin to 

 develop into stems. 



Bulbs. A bulb consists of a modified under-ground stem. 

 Leaves, thickened with stored foods, grow from this stem and 

 closely overlap each other to form the scales of the bulb. A 

 terminal bud growing from the tip of the stem is in the center 

 of the scalelike leaves. If a bulb is cut, the parts of an entire 

 plant may be seen. When planted, the embryo stem absorbs 

 food from the inclosing thickened leaves, sprouts, and develops 

 into an elongated stem bearing true leaves. As the stem 

 elongates, it sends up the leaves and flower blossom above the 

 ground. The true leaves manufacture more food than is needed 

 and the surplus is sent down to the under-ground stem, where it 

 is again stored to form another bulb. Sometimes, more than 

 one bulb will be formed. Onions, tulips, and some lilies are 

 examples of plants that may be propagated by bulbs. A col- 

 lection of bulbs may be seen in the narcissus. Bulbs are fre- 

 quently dug up from the soil so they will not freeze in winter. 

 Before they are again planted, they are separated from each 

 other and planted singly. 



