142 CONSERVATIVE ORGANS. [LECT. IV. 



the cicatrizations bearing a fancied resemblance 

 to impressions of a seal. 



a. The Contorted root (Radix contorta), al- 

 though it cannot strictly be regarded as an articu- 

 lated root, yet, it may be classed with propriety 

 m. as a modifica- 



tion or variety 

 of the kneed 

 root. TheBistort, 

 Polygonum Bis- 

 torta (fig. m), 

 affords the best 

 example of it, the 

 name of the plant 

 having originated 



in the double turn which the root takes. The 

 caudex of the root, which is , perennial, is a re- 

 servoir of nutriment for the annual renewal 

 of the herbage. 



3. The Necklace-like root (Radix monillformis) 

 (fig. n) is an articulated 

 root with nodular joints, 

 united together so as to 

 resemble beads in a neck- 

 lace ; as in Tall Meadow 

 Oat, Avena elatior nodosa. 



Such are the general forms of roots, and the 



