MODE OF LIFE IN PERENNIALS. 



31 



76. In some perennial herbs, prostrate stems or branches 

 under gronnd are thickened with tliis store of nourishment for 

 their whole length, making stout RootstocJcs, as they are called ; as 

 in Sweet Flag, Solomon's Seal (Fig. Q'^), and Iris, or Flower-de- 

 Luce (Fig. G4). These are perennial, and grow on a little way 

 each year, dying off as much behind after a while ; and the newer 

 parts every year send out a new set of fibrous roots. The buds 

 which rootstalks produce, and the leaves or the scales they bear, 

 or the scars or rings which mark where the old leaves or scales 

 have fallen or decayed away, all plainly show that rootstocks are 

 forms of stem, and not roots. The large round scars on the root- 

 stock of Solomon's Seal, which give the plant its name, (from 

 their looking like impressions of a seal,) are the places from 

 ■which the stalk bearing the leaves and flowers of each season 

 has fallen off in autumn. Fig. G3, a is the bud at the end, to 

 make the growth above ground next spring ; b is the bottom of 

 the stalk of this season ; c, the scar or place from which the stalk 

 of last year fell ; d, that of the year before ; 

 and c^ tliat of two years ago. \VW 



11 . Finally, the nourishment for the next 

 vear's G:rowth may be deposited in the leaves • - '^i.^^^"->;v: 



themselves. Sometimes it occupies all iho. '^^^■i'\''^^'''^\^^^'l,X\ 

 leaf, as in the Houseleek (Fig. Q>b) and other 



fleshy i^lants. Here the close ranks of the 

 thickened leaves are wholly above ground. 

 Sometimes the deposit is all in the lower 

 end of the leaf, and on the ground, or un- 

 derneath, as in common Bulbs. Take a 

 "White Lily of the gardens, for example, in 

 the fall, or in spring before it sends up the 

 stalk of the season (Fig. C6). From the 

 bottom of the bulb, roots descend into the 

 soil to absorb moisture and other matters 

 from it, while, above, it sends up leaves to digest and convert these matters into 

 real nourishment. "As fast as it is made, this nourishment is carried down to the bot- 



es 



Houseleek. 



