94 



PLANT LIFE. 



nature. If shoots, they will usually be subtended by a leaf; 



if leaves, they will often have a bud or a shoot in their axils. 



Thorns or tendrils which do 

 not arise at the nodes are 

 reckoned as shoots. 



117. Duration. — Shoots are 

 either annual, biennial, or per- 

 ennial. If the entire shoot dies 



Fig. 106. 



Fig. 107. 



Fig. 106. — A, upper part of a plant of Polygonum vivi/>arum, showing flower cluster, 

 the flowers in lower half being replaced by tubers. Two- thirds natural size. B, a 

 fallen tuber. Magnified about 3 diam. C, a plantlet growing from tuber. Natural 

 size. — After Kerner. 



Fig. 107. — A portion of the stem of white bryony, B, from which a tendril, ux, arises 

 near the leaf stalk, b, and the bud, k. u, rigid portion of tendril ; the portion between 

 u and the portion x, clasping the support, A , has become coiled into a spiral which 

 reverses the direction of the coils at w and w' . Nearly natural size. — After Sachs. 



this generally involves the death of the whole plant, though 

 new adventitious shoots may arise from the roots, as in 

 sweet potatoes. In many plants, in which the shoot seems 



