IX. 



POLYMORPHISM. 



A GREAT number of very interesting facts have during late 

 years been brought to light of the different forms which fungi 

 assume in the course of their development. At the same time, 

 we fear that a great many assumptions have been accepted for 

 fact, and supposed connections and relations between two or 

 three or more so-called species, belonging to different genera, 

 have upon insufficient data been regarded as so many states or 

 conditions of one and the same plant. Had the very pertinent 

 suggestions of Professor de Bary been more generally acted 

 upon, these suspicions would have been baseless. His observa- 

 tions are so valuable as a caution, that we cannot forbear prefacing 

 our own remarks on this subject by quoting them.* In order 

 to determine, he says, whether an organic form, an organ, or an 

 organism, belongs to the same series of development as another, 

 or that which is the same is developed from it, or vice versa, 

 there is only one way, viz., to observe how the second grows out 

 of the first. We see the commencement of the second begin as 

 a part of the first, perfect itself in connection with it, and at 

 last it often becomes independent ; but be it through spontaneous 

 dismembering from the first, or that the latter be destroyed 

 and the second remains, both their disunited bodies are always 

 connected together in organic continuity, as parts of a whole 

 (single one) that can cease earlier or later. 



By observing the organic continuity, we know that the apple 

 IB the product of development of an apple-tree, and not hung on 



* De Bary, iu " Quarterly German Magazine" (1872), p. 197. 



