OF DIMORPHIC AND TBIHQRPHIC PLANTS. 403 



illegitimate plants, as described under Exp. XXII., and yielded an 

 average, from eight capsules, of 122'5 seeds, with a maximum of 

 149 and a minimum of 84. Hence this plant produced no less 

 than 131 per cent, of the normal standard. 



Class V. — Illegitimate plants from the mid-styled form, fer- 

 tilized hy pollen from the shorter stamens of the long -styled form. 



I raised from this union twenty-five plants, which proved to be 

 seventeen loug-styled and eight mid-styled, but not one short- 

 styled. None of these plants were in the least dwarfed. I exa- 

 mined, during the highly favourable season of 1866, the pollen of 

 four plants : in one mid-styled plant, some of the anthers of the 

 longer stamens Avere contabescent, but in the other anthers the 

 pollen-grains were mostly sound, as they were in all the anthers 

 of the shorter stamens ; in two other mid-styled and in one long- 

 styled plant many of the pollen grains were small and shrivelled ; 

 and in the latter plant as many as a fifth or sixth appeared to be 

 in this state, I counted the seeds in five plants (Exp. XXYI. to 

 XXX.), of which two were moderately sterile and three fully 

 fertile. 



-Er^. XXVI. — This mid-styled plant was freely and* legitimately 

 fertilized, during the rather unfavourable year 1864^ by numerous 

 surrounding legitimate and illegitimate plants. It yielded an aver- 

 age, from ten capsules, of 83'5 seeds, with a maximum of 110 and 

 a minimum of 64, thus attaining 64 per cent, of the normal fer- 

 tility. During the highly favourable year 1866, it was freely and 

 legitimately fertilized by illegitimate plants belonging to the pre- 

 sent Class and to Class IV., and yielded an average, from eight 

 capsules, of 86 seeds, with a maximum of 109 and a minimum of 

 61, and thus attained 66 per cent, of the normal fertility. This was 

 the plant with some of the anthers of the longer stamens con- 

 tabescent as above mentioned. 



Exp. XXVII. — This mid-styled plant, fertilized during 1864 in 

 the same manner as the last, yielded an average, from ten capsules, 

 of 99*4 seeds, with a maximum of 122 and a minimum of 53, thus 

 attaining to 76 per cent, of the normal fertility. If the season 

 had been more favourable, its fertility would probably have been 

 somewhat greater, but, judging from the last experiment, only in 

 a slight degree. 



JExp, XXVIII.— This mid-styled plant, when legitimately ferti- 

 lized during the faA^ourable season of 1866, ill the manner de- 

 scribed under Exp- XXVI., yielded an average, from eight capsules, 

 of 89 seeds, with a maximum of 119 and a minimum of 69, thus 



