228 ILLEGITIMATE OPPSPEING OP Chap. V, 



these plants was greatly impaired. Tke loss is not 

 correlated with the colour of the flower ; and it was to 

 ascertain this point that I made so many experiments. 

 As the parent-plant growing in Edinburgh was found 

 by Mr. Scott to be in a high degree sterile, it may 

 have transmitted a similar tendency to its offspring, 

 independently of their illegitimate birth. I am, how- 

 ever, inclined to attribute some weight to the illegiti- 

 macy of their descent, both from the analogy of other 

 cases, and more especially from the fact that when the 

 plants were legitimately fertilised with pollen of the 

 common primrose they yielded an average, as may be 

 seen in the table, of only 5 more seeds than when 

 illegitimately fertilised with the same pollen. Now we 

 know that it is eminently characteristic of the illegiti- 

 mate offspring of Primula Sinensis that they yield but 

 few more seeds when legitimately fertilised than when 

 fertilised with their own-form pollen. 



Primula veris, Brit. Fl. 



Var. officinalis of Linn., P. officinalis of Jacq. 



Seeds from the short-styled form of the cowslip 

 fertilised with pollen from the same form germinate 

 so badly that I raised from three successive sowings 

 only fourteen plants, which consisted of nine short- 

 styled and five long-styled plants. Hence the short- 

 styled form of the cowslip, when self-fertilised, does not 

 transmit the same form nearly so truly as does that 

 of P. Sinensis. From the long-styled form, always 

 fertilised with its own-form pollen, I raised in the 

 first generation three long-styled plants, — from their 

 seed 53 long-styled grandchildren, — ^from their seed 

 4 long-styled great-grandchildren, — ^from their seed 

 20 long-styled great-great-grandchildren, — and lastly, 



