188 



A TEXTBOOK OF BOTANY 



[Ch. IV,10 



whence their botanical name of rootstocks; but they are 

 always distinguished by the presence of nodes and rudi- 



Fig. 130. — Stolon of Black Raspberry. (From Bailey.) 



mentary scale-like leaves. Such rootstocks often accumu- 

 late food, thus tending towards new organs, which we may 

 best consider in the following section. 



There also occur a kind of traveling stems. The very 

 slender woody stems of the Brambles bend over and touch 



Fig. 131. — Sempervivum soboliferum, showing typical offsets. 

 (From Kerner.) 



the ground at their tips, where they take root ; and thus the 

 plants form dense and ever advancing thickets (Fig. 130). 



