THE ROOT. 



13 



Tuberous, or Knotted root, Fig. 6, (Ra- 

 dix tuberosa.) The best examples con- 

 sist of knobs, connected together by 

 strings or fibres. Some of these are pe- 

 rennial, as the Jerusalem artichoke, (He- 

 liantkus tuberosus.) Others are annual, 

 as the Potato, (Solanum tuberosum.) 



Necklace, or Moniliform root. This is 

 a tuberous root so regularly connected together by its inter- 

 vening cords, as to resemble a necklace. Hence the name 

 moniliform, from monile, a necklace. 



Fig. * 



Sometimes many small tubers or knots, 

 grow in clusters, or are scattered on the 

 radical fibres, in a manner resembling 

 grains. These are called granulated roots, 

 Fig. 7, (Radix granulata.} Many of the 

 grasses have this kind of root, also Wood- 

 sorrel, (Oxalis acetosella.) 



Hand-shaped, or Palmated root, Fig. 8, 

 (Radix palmata.} This consists of oblong 

 fleshy tubers, which are connected above, 

 but parted below, into divisions resembling 

 the fingers. Ex. Orchis, Dahlia. 



Bulbous root, (Radix bulbosa.) These are of several 

 kinds, viz. 



Fig. 9. 



Solid bulb, Fig. 9, consisting of a uniform, 

 fleshy substance. Ex. Crocus, Erythronium, 

 Turnip. These differ from tuberous roots in 

 there being only one tuber attached to a plant, 

 and in other respects, as will be seen directly. 



Tunicated root, Fig. 10. This consists of ma- 

 ny concentric layers placed one over, or without 

 trie other. Ex. Onion, (Allium cepa.) 



Many plants with solid bulbs inhabit sandy bar- 

 ren places, and over the face of which they are dissemina 



