KINDS OF ROOTS. 35 
and so make props or additional trunks. Growing in this way, there is no limit to 
the extent of the branches, and a single Banyan will spread over several acres of 
ground and have hundreds of trunks all made from aerial roots. . 
86. Aerial Rootlets, or such roots on a small scale, are produced by several woody 
vines to climb by. English Ivy, our Poison Ivy, and Trumpet-Creeper are well- 
known cases of the sort. . 
87. Air-Plants, Roots which never reach the ground are also produced by certain 
plants whose seeds, lodged upon the boughs or trunks of trees, high up in the 
air, grow there, and make an 
Epiphyte, as it is called (from 
two Greek words meaning 
a plant on a plant), or an 
Air-Plant. The latter name 
refers to the plant’s getting 
its living altogether from the 
air; as it must, for it has no 
connection with the ground 
at any time. And if these 
plants can live on air, in this 
way, it is easy to understand 
that common vegetables get 
part of what they live on di- 
rectly from the air. In warm 
countries there are many very 
handsome and curious air- 
‘plants of the Orchis family. 
A great number are culti- 
vated in hot-houses, merely 
fixed upon pieces of wood we 
and hung up. They take no t Air-plants of the Orcbis family. 
nourishment from the boughs of the tree they happen to grow upon. 
88. Parasitic Plants are thbse which strike their roots, or what answer to roots, 
into the bark or wood of the species they grow on, and feed upon its sap. The 
Mistletoe is a woody parasitic plant, which engrafts itself when it springs from the 
seed upon the branches of Oaks, Hickories, or other trees. The Dodder is a com~ 
