548 Mutations 



origin for all the observed individuals of either 

 strain. But whether, besides this, similar 

 strains are produced anew by the old lamarchi- 

 ana group, it is impossible to decide on the sole 

 ground of these field-observations. 



The same holds good with the other novelties. 

 Even if one of them should germinate repeated- 

 ly, without ever opening its flowers, the possi- 

 bility could not be excluded that the seeds might 

 have come originally from the same capsule but 

 lain dormant in the earth during periods of un- 

 equal length. 



Other objections might be cited that can only 

 be met by direct and fully controlled experi- 

 ments. Next to the native locality comes the ex- 

 perimental garden. Here the rule prevails that 

 every plant must be fertilized with pollen of its 

 own, or with pollen of other individuals of 

 known and recorded origin. The visits of in- 

 sects must be guarded against, and no seeds 

 should be saved from flowers which have been 

 allowed to open without this precaution. Then 

 the seeds of each individual must be saved and 

 sown separately, so as to admit of an apprecia- 

 tion, and if necessary, a numerical determina- 

 tion of the nature of its progeny. And last but 

 not least the experiments should be conducted 

 in a similar manner during a series of successive 

 years. 



