CHAP. IV. OXALIS ROSEA. 177 



flowers illegitimately fertilised yielded 12 capsules, 

 containing on an average 28.58 seeds. Therefore the 

 fertility of the six legitimate to that of the twelve 

 illegitimate unions, as judged by the proportion of 

 flowers which yielded capsules, is as 100 to 15, and 

 judged by the average number of seeds per capsule, as 

 100 to 49. This plant, in comparison with the two 

 South American species previously described, produces 

 many more seeds, and the illegitimately fertilised flow- 

 ers are not quite so sterile. 



Oxalis rosea. Hildebrand possessed in a living state 

 only the long-styled form of this trimorphic Chilian 

 species.* The pollen-grains from the two sets of 

 anthers differ in diameter as 9 to 7.5, or as 100 to 83. 

 He has further shown that there is an analogous dif- 

 ference between the grains from the two sets of an- 

 thers of the same flower in five other species of Oxalis, 

 besides those already described. The present species 

 differs remarkably from the long-styled form of the 

 three species previously experimented on, in a much 

 larger proportion of the flowers setting capsules when 

 fertilised with their own-form pollen. Hildebrand fer- 

 tilised 60 flowers with pollen from the mid-length 

 stamens (of either the same or another flower), and 

 they yielded no less than 55 capsules, or 92 per cent. 

 These capsules contained on an average 5.62 seeds; 

 but we have no means of judging how near an approach 

 this average makes to that from flowers legitimately 

 fertilised. He also fertilised 45 flowers with pollen 

 from the shortest stamens, and these yielded only 17 

 capsules, or 31 per cent., containing on an average 

 only 2.65 seeds. We thus see that about thrice as 

 many flowers, when fertilised with pollen from the 



* ' Monatsber. der Akad. der Wiss. Berlin,' 1866, p. 372. 



