CHAPTEE VII 



CONCLUSION 



IT will be useful, at the conclusion of our series of types, 

 to sum up very briefly what we have learnt from them, 

 with reference especially to the relationships of the 

 groups which they represent. Throughout the book we 

 have followed on the whole a descending order, proceed- 

 ing from the more complex to the more simple, though 

 there have been many exceptions to this rule, because it 

 is impossible to arrange any set of plants in a single 

 linear series, whether according to increasing or decreas- 

 ing complexity. 



In the present summary we will follow the reverse 

 order, starting where we left off, with the lowest forms, 

 following up the various lines of affinity, and concluding 

 with the highest plants, with which we began in Part I. 

 This is the naturafsuccession, and the attempt to follow 

 it will at any rate teach us how complicated the relation- 

 ships are, and how difficult it is to arrange naturally even 

 a few types such as ours. 



The two groups with which we concluded the series, 

 and with which we therefore begin our summary, have no 

 clear and evident affinities with any of the rest. As 

 regards the Myxomycetes, it is doubtful whether any such 

 relationship exists at all. These organisms have attained 



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