450 MR. C. DABWIN OK SPECIFIC DIFFERENCES IN PRIMULA. 



ascertain whether the Bardfield oxlip, when crossed with the Cow- 

 slip and Primrose, behaved like a distinct species; for if it can be 

 clearly proved not to be a hybrid, and if the Cowslip and Primrose 

 are specifically distinct, I presume that no one will any longer 

 doubt that the P. elatior is likewise distinct. The following Table 

 shows the fertility of the four unions between the two forms of 

 this dimorphic species : 



Table VI. 



JPrimula elatior or Bardfield Oxlip. 



Natou-e of union. 



Short-styled form, by pollen ofl 

 long-styled. Legitimate union J 



Long-styled form, by pollen of "1 

 short-styled. Legitimate union j 



Short-styled form, by own-form 1 

 pollen. Illegitimate union j 



Long-styled form, by own-form 

 pollen. Illegitimate union 



I 



Number of 

 flowers fer- 

 tilized. 



Number of 

 good capsules. 



10 



8 



10 



6 



17 



3 



20 



4 



a 





© CO 



>-« 



> 



O 



si 





PI o 



"3 



477 



46-5 



61 



1213 



27-7 



G2 



19 



49 & 

 40* 





S 





.s'Z 



"3 



to 



i- 



37 



34 



9 



2 



* Bat these seeds were so poor and small that they covdd hardly have 

 germinated. 



w 



Botti forma of this plant, when protected from insects, sponta- 

 neously produced a few capsules, some of which contained no seed, 

 and the others, only six in number, included on an average only 

 7*8 seeds, many of which were bad. The foregoing Table clearly 

 shows that P. elatior resembles in the nature of its fertility the 

 many other species of Frimula which have been experimented on 

 by Mr. J. Scott f and myself. On the other hand, this plant dif- 

 fers almost as widely as is possible from the common Oxlip, both 

 forms of which when legitimately fertilized (see Table I.) were 

 absolutely barren, whereas the two forms of P. elatior when simi- 

 larly fertilized yielded averages of 47'7 and 4G*5 seeds. The pol- 

 len differs in condition in an equal degree ; for in two out of the 

 three short-styled plants of the common Oxlip all the grains, and 



t ** On the Functions of the Reproductive Organs in the Primulaceae," Joum. 

 Proc. Linn. Soc. vol. viii. (1864) p. 78. 



