92 EVOLUTION OF BRITISH CATTLE 



a few were triennial ; best of all, it showed what 

 can hardly be otherwise described than as new 

 species in the making. 



" It is possible that the prolific ;multiplication 

 in a new environment may have had something 

 to do with the awakening of the impulsive 

 mutability. 



"In 1887, a year after his discovery of the 

 potato-field, De Vries found two well-defined 

 new forms — a short-styled O. brevistylis and a 

 beautiful smooth-leaved O. Icevifolia — distinguish- 

 able from the parent in many details. He hailed 

 these as two new ' elementary species,' and he 

 applied one of the crucial tests of specific or sub- 

 specific rank : Did they breed true ? He found 

 that it was so ; from their self-fertilised seeds 

 similar forms arose. Neither of the two new 

 forms was represented in the herbaria at Leyden, 

 Paris, or Kew ; neither had been described in 

 the literature of Onagracecs, They seemed to 

 be distinctly new. It is interesting to note that 

 in 1887 there were few examples of these two 

 new elementary species, and that each occurred 

 on a single plot on the field. The impression 

 conveyed was that each had arisen — by a 

 sudden mutation — from the seed of an individual 

 parent. 



** The next chapter in the famous investiga- 

 tion began with a transference of samples of the 

 new forms and the parent stock — partly as plants 



