40 

 IS MONOTROPA UNIFLORA A PARASITES 



Geokge Baptie, M.A., M.B. 



(Head, 3rd March, 1S87.) 



This note had itSi^rigin in a chance question put at one of ^Ir. R. 

 B. Whyte's admirable afternoon lectures on botany. The discussion 

 which followed showed that members of the Ottawa Field-Naturalists' 

 Club were divided in opinion in regard to the parasitism of Monotropa 

 unijlora, or Indian pipe, some holding the plant to be a parasite, others 

 disposed to believe that it was not. Now, what is a parasitel 

 It is desirable to know precisdy what is meant by this term, because 

 one person may mean one thing by it, another person may understani 

 a different thing. To settle the usage a number of authors were 

 examined. They mean by a parasite a plant which has an organic 

 connection with another living plant, and thus derives nourishment from 

 the latter. Parasites differ in the extent to which they draw sustenance 

 from the plant to which they are attached. The relation may be 

 illustrated by what is commonly known to be the relation between 

 animals and their animal parasites. The parasitic plant bears the same 

 relation to another plant that a louse or a tapeworm bears to the 

 animal which supports it. A plant parasitic on another may be said 

 to steal a part or the whole of its living, its food, from the plant to 

 which it is attached. 



To answer the question at the head of this note, the following plan 

 can be adopted : 



We can consult standard bcoks. This has been done. The 

 authors do not agree. Macoun, Spotton, Wood, Gray, Goodale, and 

 Balfour either positively assert that Monotropa Unijlora is a parasite, 

 or their language would lead a reader to believe it to be parasitic. 

 Gray is self contradictory. Sachs speaks of monotropa as a saprophyte, 

 and therefore not parasitic. By saprophytes he means plants which 

 make use in their growth and development of the materials of other 

 plants, dead ones, which are already in a state of decomposition. The 

 position of Murray is this : " No case has yet been satisfactorily made 

 out for the parasitism of this group (monotropa)." 



