76 



THE STEM. 



b. In regard to duration, trees differ much, some attaining their growth in a few 

 years and immediately decaying, while on the contraiy, the ordinary age of trees 

 is beyond the age of man, and some outlive many generations, as the oak, pine. * 



190. The SUCKER is a branch proceeding from the stem, or 

 root, beneath the surface, producing leaves, &c., and throwing 

 out roots from its own base, becoming an independent plant. 

 Ex. rose, raspberry. 



191. An OFFSET is a short, lateral branch, terminated by a 

 cluster of leaves, and capable of taking root when separated 

 from the parent plant. Ex. house-leek (Sempervivum). 



192. A STOLON is a branch which proceeds from an elevated 

 part of the stem, and afterwards, descending to the earth, takes 

 root, sends up new shoots, and finally becomes a new plant. It 

 differs from the sucker, in originating above the ground and not 

 below it. 



FIG. 24. — Forms of ihe stem ; 1, Fragaria; 2, Vitis ; b, tendrils ; 3, cirrhose leafof Pisum ; 

 4, Pyrola ; 5, sucker. 



193. A plurality of stems, or tiTinks, is observed in a few spe- 

 cies of trees growing in tropical regions. The Banyan (Ficus 



*It is recorded that a live oak, in Louisiana, lived 1000 years ; a sycamore in Palestine, 

 1050 yearg ; a pine in Asia Minor, 1800 years ; a cedar on Mt. Lebanon, 2120 years, and the 

 great chestnut on Mt. Etna, 2600 years. It is also supposed that there are yet living, in the 

 " garden of Gelhsemane," some of the olives which wimessed our Saviour's passion ; and 

 at Terni, Italy, is an olive plantation supposed to have existed since the age of Pliny. 



