464 On the Latent Capacity for Mutation. 



exclusively on the extensiveness of the crop. Whenever 

 I, had the opportunity of sowing on a large scale, either 

 with seeds from the field at Hilversum (1889) or, in my 

 own families, with the seeds of a few seed parents, espe- 

 cially in the year 1895 (p. 224 and p. 262), a large num- 

 ber of mutations appeared. Their rarity in other years 

 and cultures can therefore only be attributed to the small 

 scale on which the sowings were made; for on a few 

 square meters we cannot expect to get many mutations 

 if the seeds are not sown very close and the crops are not 

 examined every day. 



Thirdly, the small number of the different mutations 

 which appeared. By no means does every conceivable 

 deviation occur. Thus there arose no white flowers, no 

 glabrous or unbranched individuals, no linear petals,^ no 

 trace of petalomany or apetaly and so forth. Even of 

 the two new species which w^ere found in the field at 

 Hilversum, 0. hrevistylis and 0. lacvifolia, not a single 

 example occurred in my cultures. 



We are led to the same conclusion by a consideration 

 of the more or less incompletely developed individuals^ 

 of the new species which sometimes seem to constitute 

 transitional forms. For these arise in my cultures not 

 before the mutants, but simultaneously or more com- 

 monly only after them. Each mutation is as completely 

 developed when it first appears as afterwards. When a 

 mutation is grown through many generations and on 

 a very large scale its various representatives conform 

 to exactly the same type. I possess photographs and de- 

 scriptions of my mutations from the first year of their 

 appearance and find that nothing has been added to, or 



^ "Forma cruciata" as found in Oenothera cruciafa Nuff. and 

 some others. 



