'Slew Species of Oenothera 525 



of young seeds. The capsule, when ripe, opens 

 at its summit with four valves, and contains 

 often from two to three hundred seeds. A hun- 

 dred capsules on the main stem is an average 

 estimate, and the lateral branches may ripen 

 even still more fruits, by which a very rapid dis- 

 semination is ensured. 



This striking species was found in a locality 

 near Hilversum, in the vicinity of Amsterdam, 

 where it grew in some thousands of individuals. 

 Ordinarily biennial, it produces rosettes in the 

 first, and stems in the second year. Both the 

 stems and the rosettes were at once seen to be 

 highly variable, and soon distinct varieties 

 could be distinguished among them. 



The first discovery of this locality was made 

 in 1886. Afterwards I visited it manv times, 

 often weekly or even daily during the first few 

 years, and always at least once a year up to 

 the present time. This stately plant showed the 

 long- sought peculiarity of producing a number 

 of new species every year. Some of them were 

 observed directly on the field, either as stems 

 or as rosettes. The latter could be transplanted 

 into my garden for further observation, and 

 the stems yielded seeds to be sown under like 

 control. Others were too weak to live a suffi- 

 ciently long time in the field. They were dis- 

 covered by sowing seed from indifferent plants 



