20 



BOTANY. 



Some of the common varieties of tap-root are easily 

 recognized. Fusiform or spindle-shaped roots, like Fig. 

 62, and napiform or turnip-shaped roots, like Fig. 63, are 

 familiar to every one. 



In the case of fibrous roots, we have seen (Fig. 60) 

 that the stem divides at once at its base into a mass of 

 slender branches or rootlets. These fibers often become 

 enlarged, and, when the swellings take the form seen in 



FIG. 66. 



FIG. 67. 



Fig. 64, the root is said to be tuberculated, and each en- 

 largement is called a tubercule. Sometimes these tuber- 

 cules resemble the human hand (see Fig. 65), when they 

 are said to be palmated tubercules. When a number of 

 tubercules arise from a common point, the root is said to 

 '^fasciculated (Fig. 66). When the fibers have numerous 

 small swellings or nodules (Fig. 67), the root is nodulose. 



