36 



ROOTS. 



[section 



Spindle ->ihaped, or Fusiform, wlicu thickest iu the iniddlc aud tapering to 

 both ends; as the cuminou Kadish (Fig. 85). 



70. These cxaiiij)les are uf primary roots. It will be seen that turnips, 

 carrots, and tue like, are not pure root throughout : for the caulicle, from 

 tlie lower end of which the root grew, partakes or me thickening, jjcrhaps 

 also some joints of stem above : so the bud-bearing aud growing top is 

 stem. 



77. A fine example of secondaiy roots (67), some of which remain fibrous 

 for absorption, while a few thicken aud store up food for the next season's 

 growth, is furnished by the Sweet Potato (Fig. 86). As stated above, 

 these are used for ])ropagatiou by cuttings; for any part will produce ad- 

 ventitious buds aud shoots. The Dahlia produces fascicled (i. e. clustered) 

 fusiform roots of the same kind, at the base of the stem (Fig. 87) : but 

 these, like most roots, do not produce adventitious buds. The buds by 

 which Dahlias are propagated beloug to the surviving base of the stem 

 above. 



78. Anomalous Roots, as they may be called, are those which subserve 

 other uses tliau absorption, food-storing, and fixing the plant to the soil. 



Aerial Roots, i. e. those that strike from stems in tlie open air, are, 

 common in moist and wann .^ 



climates, as in the Mangrove 

 which reaches tlie coast of 

 Florida, t he Banyan, and, less 

 strikingly, in some lierbace- 

 ous plants, such as Sugar 

 Cane, and even in Indian 

 Corn. Such roots reach the 

 ground at leugtli, or tend to 

 do so. 



Aerial Rootlets are abun- 

 dantly produced by many 

 climbing plants, such as the 

 Ivy, Poison Ivy, Trumpet 

 Creeper, etc., springing from 

 the side of stems, which they 

 fasten to trunks of trees, 

 walls, or other supports. 

 These are used by the plant 

 for climbing. 



79. Epiphytes, or Air- 

 Plants (Fig. 88), are called by the former name because comraonly growicg 



Fig. 88. Epiphytes of Florida and Gonrjiia. viz., Epidendrum conopsenm, a 

 .small Orchid, and Tillandsia nsncoides, the .so-called Long Mo.ss or Black Moss, 

 which is no moss, but a flowering plant, also T. recurvata ; ou abouj,h of Live Oak. 



