, 



Chap. II. THE COMMON OXLIP. 57 



the primrose, when legitimately and naturally ferti- 

 lised, yield on an average many more seeds per capsule 

 than the cowslip, namely, in the proportion of 100 to 

 55. When illegitimately fertilised they are likewise 

 I more fertile than the two forms of the cowslip, as shown 



by the larger proportion of their flowers which set cap- 

 sules, and by the larger average number of seeds which 

 the capsules contain. The difference also between the 

 number of seeds produced by the long-styled and short- 

 styled flowers of the primrose, when both are illegiti- 

 mately fertilised, is greater than that between the num- 

 ber produced under similar circumstances by the 

 two forms of the cowslip. The long-styled flowers of 

 the primrose when protected from the access of all in- 

 sects, except such minute ones as Thrips, yield a con- 

 siderable number of capsules containing on an average 

 19.2 seeds per capsule; whereas 18 plants of the long- 

 styled cowslip similarly treated did not yield a single 

 seed. 



The primrose, as every one knows, flowers a little 

 earlier in the spring than the cowslip, and inhabits 

 slightly different stations and districts. The primrose 

 generally grows on banks or iji woods, whilst the cow- 

 slip is found in more open places. The geographical 

 range of the two forms is different. Dr. Bromfield re- 

 marks * that " the primrose is absent from all the in- 

 terior region of northern Europe, where the cowslip is 

 indigenous." In Norway, however, both plants range 

 to the same degree of north latitude, f 

 * The cowslip and primrose, when intercrossed, be- 



* ' 



Phytol 



1 UJ MUUglBl, VU1. 111., p. \JtT*. Kl I IttUVC, -K-rro, wm*.. «• f Z Zr 



t H. Lecoq, ' G6ograph. Bot. de With respect to the rarity of P. 



F Europe,' torn, viii., 1858, pp. 141, veris in western Scotland, see 



144. See also ' Ann. and Mag. of H. C. Watson, ' Cybele Britan- 



Nat. Hist.,' ix., 1842, pp. 156, 515. nica,' ii. p. 293. 

 Also Boreau, ' Flore du centre de 



