236 ILLEGITIMATE OFFSPRING OF CHAP. V. 



Mr. Scott, with the parent-plant. Lastly, twelve plants 

 were in appearance short-styled: but they varied much 

 more in the length of their pistils than ordinary short- 

 styled cowslips, and they differed widely from the latter in 

 their powers of reproduction. Their pistils had become 

 short-styled in structure, whilst remaining long-styled in 

 function. Short-styled cowslips, when insects are excluded, 

 are extremely barren: for instance, on one occasion six 

 fine plants produced only about 50 seeds (that is, less than 

 the product of two good capsules), and on another occasion 

 not a single capsule. Now, when the above twelve appar- 

 ently short-styled seedlings were similarly treated, nearly 

 all produced a great abundance of capsules, containing 

 numerous seeds, which germinated remarkably well. 

 Moreover three of these plants, which during the first year 

 were furnished with quite short pistils, on the following 

 year produced pistils of extraordinary length. The greater 

 number, therefore, of these short-styled plants could not 

 be distinguished in function from the equal-styled variety. 

 The anthers in the six equal-styled and in the apparently 

 twelve short-styled plants were seated high up in the 

 corolla, as in the true short-styled cowslip ; and the pollen- 

 grains resembled those of the same form in their large size, 

 but were mingled with a few shrivelled grains. In function 

 this pollen was identical with that of the short-styled cow- 

 slip; for ten long-styled flowers of the common cowslip, 

 legitimately fertilised with pollen from a true equal-styled 

 variety, produced six capsules, containing on an average 

 34.4 seeds; whilst seven capsules on a short-styled cowslip 

 illegitimately fertilised with pollen from the equal-styled 

 variety, yielded an average of only 14.5 seeds. 



As the equal-styled plants differ from one another in 

 their powers of reproduction, and as this is an important 

 subject, I will give a few details with respect to five of 

 them. First, an equal-styled plant, protected from insects 

 (as was done in all the following cases, with one stated 

 exception), spontaneously produced numerous capsules, 

 five of which gave an average of 44.8 seeds, with a maxi- 

 mum in one capsule of 57. But six capsules, the product 

 of fertilisation with pollen from a short-styled cowslip (and 

 this is a legitimate union), gave an average of 28.5 seeds, 

 with a maximum of 49 ; and this is a much lower average 



