ANATOMY STUDY OF ROOTS 55 



Such a solution contains everything necessary for the growth of a 

 plant. Note how the bulb produces water roots, which obtain from 

 the solution the substances required by the plant for its growth. Observe 

 the growth of leaves and flowers. This experiment shows that roots, 

 which under natural conditions live in soil, can change their mode of 

 life and become water roots. 



EXPT. 41. Cut a slip from any plant, (the garden Geranium will do), 

 so as to leave at least three nodes with leaves and one without. Place 

 the slip in a bottle with some of the solution used in the last experiment. 



Observe that roots develop in the water from the nodes. Keep the 

 bottle warm ; it will soon be filled .with roots. These roots are 

 adventitious and aquatic. 



Parasitic Roots. The roots of those plants which pene- 

 trate a host plant, and extract nourishment from it, are called 

 parasitic. The Mistletoe, which grows on Apple, Fir, and 



FIG. 73. St, stem of Apple. S, shoot of Mistletoe ; R, roots of Mistletoe. 

 (One-twelfth nat. size.) 



Poplar trees is a parasite. Mistletoe is very plentiful in our 

 homes about Christmas time, and most persons know its berries. 

 Thrushes feed on these berries, and the seeds enclosed in the 

 fruit are protected from the digestive juices by a hard covering. 

 They consequently pass out of the digestive tube without 

 undergoing any change ; the droppings of the Thrush are 



