CHAP. I. 



PEIMULA ELATIOE. 



33 



The results of my trials on the relative fertility of 

 the two forms, when legitimately and illegitimately 

 fertilised, are given in the following table : 



TABLK 8. 

 Primula elatior. 



* These seeds were so poor and small that they could hardly have germinated. 



If we compare the fertility of the two legitimate 

 unions taken together with that of the two illegitimate 

 unions together, as judged by the proportional number 

 of flowers which when fertilised in the two methods 

 yielded capsules, the ratio is as 100 to 27 ; so that by 

 this standard the present species is much more sterile 

 than P. veris, when both species are illegitimately fer- 

 tilised. If we judge of the relative fertility of the two 

 kinds of unions by the average number of seeds per 

 capsule, the ratio is as 100 to 75. But this latter 



