324 STRUCTURE AND LIFE HISTORIES 



Fig. 230), and its close relative, the false beech-drops 

 (Monotropa Hypopitys, Fig. 231), are examples of flowering 

 plants, wholly devoid of chlorophyll, and therefore unable 

 to manufacture their food, which is absorbed entirely 

 from the humus in which they grow. Other examples 

 are Lathrcca, and the coral-root {Corallorhiza). 



Fig. 231. — False beech drops {Monotropa Hypopitys). (Photo by Elsie 

 M. Kittredge.) 



SYMBIOSIS 



305. Different Kinds of Symbiosis. — The absorption of 

 nourishment from one plant by another involves, of course, 

 the intimate association of the two organisms. Such a 

 vital association is called symbiosis (living together), and 

 we find organisms living together in all degrees of intimacy 



