544 Mutations 



Fertilizing the flowers artificially witli tlieir 

 own pollen, excluding the visiting insects by 

 means of paper bags, and saving and sowing 

 the seed of each individual separately, fur- 

 nishes all the requisites for the estimation of the 

 degree of stability of this species. In the first 

 few weeks the seed-pans do not show any un- 

 equality, and often the young plants must be re- 

 planted at wider intervals, before anything 

 can be made out with certainty. But as soon 

 as the rosettes begin to fill it becomes mani- 

 fest that some of them are more backward than 

 others in size. Soon the smaller ones show 

 their deeper green and broader leaves, and 

 thereby display the attributes of the scintillans. 

 The other grow faster and stronger and exhibit 

 all the characteristics of ordinary lamarcki- 

 anas. 



The numerical proportion of these two groups 

 has been found different on different occasions. 

 Some plants give about one-third scintillans 

 and two-thirds lama^^cJciana, while the progeny 

 of individuals of another strain show exactly 

 the reverse proportion. 



Two points deserve to be noticed. First the 

 progeny of the scintillans appears to be mutable 

 in a large degree, exceeding even the lamarcki- 

 ana. The same forms that are produced most 

 often by the parent-family are also most ordi- 



