ORGANS OF NTJTEITION. 



123 



of a number of succulent branches of nearly equal size, and ar- 

 ranged like a piece of coral {fig. 234), as in Corallorrhiza innata. 



Tuberculated Root. — -When some of the diAnsions of a root 

 become enlarged so as to form more or less rounded or egg- 

 shaped expansions {fig. 235), the root is said to be tuberculated, 

 and each enlargement is called a ticbercule. Such a root occurs 

 in various terrestrial Orchids, the Jalap plant, &c. These tuber- 

 eules must not be confounded wdth tubers, which have been 

 already described as subterranean modifications of the stem. 

 The presence of eyes or buds on the latter at once distinguishes 

 them. In many Orchids, as for instance the Orchis maculata, the 

 tubercules are di^dded at their extremities, so that the whole 

 resembles the human hand {fig. 236); they are then said to be 

 palmated, and the root is also thus termed. 



Fascicidatcd, Clustered, or Tufted Root.- — These names are 

 applied indifferently to a root which consists of a number of 



Fig. 237. 



Fig. 238. 



/- 



Fig. 237. Fasciculated roots of the Dahlia. Fig. 238. Nodulose root of 



the common Dropv/ort {SpircBa Filipendula). 



tubercules or fleshy branches arising from a common point, as in 

 the Dahlia (j?^. 237), and Bird's-nest Orchis {Neottia ]S'id2(s-avis). 

 Nodulose, Annulated, and Moniliform or Necklace-shaped 

 Roots. — These terms are applied to roots which are expanded 

 only at certain points. Thus, when the branches are enlarged 



