A'()()y.s 55 



there are others nf an iiitermccliate kiiifl, but it is 

 possible to recognise amf)nj^st common plants the 

 roots belonj4in<4' to one oi' otlu-r of ihr t)prs 1 

 lia\c (lescrilx'd. J-Or tin- purposes of stii(l\- uc 

 inav hroadi)' s^ioiip roots into classes accordinL;' to 

 their method of collcctin;4 and absorhin;^ food. 

 Thus we find one L^roup ^rowinL^ in soil and 

 feeding upon the soluble earth salts and moisture 

 of the soil. Another grouj) w ill be found growin;^^ 

 in water, like the \vater-lil\- and pond weeds. A 

 third ^M'oup simply hani^s down in space from 

 some perching;' j^lant like the tropical orchid, whilst 

 a foiu'th and ver\' small t^roup consists of parasitic 

 roots, of which a ver)' common example is the 

 mistletoe. We will now stud\' each of these 

 groups separatel}'. 



1 have alread)- spoken of some kinds of fibrous 

 roots, and ma\' add that if the root of a land plant 

 is immersed in water, it will after a time develop a 

 different kind of fibre, capable of receixing nourish- 

 ment from water instead of earth. I remember 

 seeing an instance of this in the case of a laurel 

 bush which grew near a well in our garden. We 

 had occasion to examine the water, and found that 



