HERITABLE DIFFERENCES 43 



1860, and thence it spread to the continent, where, 

 escaping from gardens, it became wild in at least 

 one locality near Hilversum, a few miles from Amster- 

 dam. Here, in an abandoned potato field, it fell under 

 the seeing eye of Hugo deVries in 1885, and now both 

 botanist and primrose are famous. 



DeVries found among these escaped plants not only 

 0. lamarckiana, but also two other kinds of mutants, 

 0. brevistylis, characterized by short-styled flowers, 

 and 0. Icevifolia, which has smooth leaves. These two 

 were entirely new species hitherto unknown at the great 

 botanical clearing-houses of Paris, Leyden, and the 

 Kew Gardens. 



Since the seeds of the (Enofhera are produced by 

 self-fertilized flowers, deVries felt safe in regarding 

 these plants as mutants rather than hybrids, and he 

 continued to study them with especial care. Trans- 

 planting the mutants along with representatives of 0. 

 lamarckicma to his private gardens in Amsterdam, 

 where it was possible to maintain them in normal 

 healthy condition, deVries was able to follow their indi- 

 vidual histories with certainty. 



The wild mutants Icevifolia and brevistylis did not 

 reappear under cultivation but he found that, out of 

 54,343 plants of the species 0. lamarckiantt grown as 

 descendants from nine original plants during eight 

 years, there appeared 837 mutants comprising seven 

 different elementary species, all of which, with the ex- 

 ception of 0. scintttlans, bred true. See table on the 

 next page. 



Some explanatory comment on this table may be 

 of value. 



