698 Mutations 



sops, petals of Nympliaea may be cited as in- 

 stances, and they are as perfectly preserved as 

 the best herbarium-specimens of the present 

 time. The petals and stamens retain their orig- 

 inal colors, displaying them as brightly as is 

 consistent with their dry state. 



Paleontologic evidence points to the same 

 conclusion. Of course the remains are incom- 

 plete, and rarely adequate for a close compari- 

 son. The range of fluctuating variability should 

 be examined first, but the test of elementary 

 species given by their constancy from seed can- 

 not, of course, be applied. Apart from these 

 difficulties, paleontologists agree in recognizing 

 the very great age of large numbers of species. 

 It would require a too close survey of geologic 

 facts to go into details on this point. Suffice it 

 to say that in more recent Tertiary deposits 

 many species have been identified with living 

 forms. In the Miocene period especially, the 

 similarity of the types of phanerogamic plants 

 with their present offspring, becomes so striking 

 that in a large number of cases specific distinc- 

 tions rest in greater part on theoretical con- 

 ceptions rather than on real facts. For a long 

 time the idea prevailed that the same species 

 could not have existed through more than one 

 geologic period. Many distinctions founded 

 on this belief have since had to be abandoned. 



