VARIATION 413 



we have been thinking for a long time what to do, or how to 

 arrange our ideas, and have yet been unable to arrive at 

 any conclusion." 



To the Dutch botanist De Vries especial credit is due for 

 his recognition of the evolutionary importance of mutations 

 and for his study of their behaviour in inheritance. It is 

 an often told story how he found, in 1886, in a potato- 

 garden near Hilversum, in Holland, a race of the Evening 

 Primrose ((Enothera lamarckiana) in which the mood was 

 all mutation. In spite of Gallon's insistence on the reality 

 of transilient variations and Bateson's marshalling of in- 

 stances of discontinuity, the tendency had grown strong to 

 dogmatise about the continuity of organic change, just as 

 previously about the fixity of species. " Natura non facit 

 saltus," they said: but De Vries discerned Natura saltatrix 

 in the Evening Primrose of Hilversum, which, by the way, 

 turns out to have been in the 18th century a wild 

 species in North America. Three points may be emphasised. 

 FirstptEat some of the mutants which De Vries's sportive 

 (Enotheras threw off, as an artist might tear sketches from 

 his note-book, were ephemeral failures, while others were 

 viable and bred true, and could not be otherwise described 

 than as species in the making, fingers searching as it were 

 for their appropriate environmental glove. Second, in many 

 cases the mutants were of particular interest because they 

 showed through and through divergences in leaf and stem 

 and flower certainly suggestive of some general disturb- 

 ance of germinal organisation. Just as if the (Enothera was 

 born again! Third, that the creativeness or sportiveness of 

 the Evening Primrose is not restricted to De Vries's partic- 

 ular race of (Enothera lamarckiana. It occurs in other 

 species of Evening Primrose, and also in snapdragon and 



