276 SUMMARY OF MEASUEEMENTS. CHAP. Vll 



(7.) Viscaria oculata.The average height of the fifteen inter- 

 crossed plants to that of the fifteen self-fertilised plants was only 

 as 100 to 97 ; but the former produced many more capsules than 

 the latter, in the ratio of 100 to 77. Moreover, the flowers on the 

 parent-plants which were crossed and self-fertilised, yielded seeds 

 on one occasion in the proportion of 100 to 38, and on a second 

 occasion in the proportion of 100 to 58. So that there can be 

 no doubt about the beneficial effects of a cross, although the 

 mean height of the crossed plants was only three per cent, above 

 that of the self-fertilised plants. 



(8.) Specularia speculum. Only the four tallest of the crossed 

 and the four tallest of the self-fertilised plants, growing in four 

 pots, were measured ; and the former were to the latter in height 

 as 100 to 98. In all four pots a crossed plant flowered before 

 any one of the self-'fertilised plants, and this is usually a safe 

 indication of some real superiority in the crossed plants. The 

 flowers on the parent- plants which were crossed with pollen from 

 another plant yielded seeds compared with the self-fertilised 

 flowers in the ratio of 100 to 72. We may therefore draw the 

 same conclusion as in the last case with respect to a cross being 

 decidedly beneficial. 



(9.) Borago officinalis. Only four crossed and four self- 

 fertilised plants were raised and measured, and the former were 

 to the latter in height as 100 to 102. So small a number of 

 measurements ought never to be trusted ; and in the present in- 

 stance the advantage of the self-fertilised over the crossed plants 

 depended almost entirely on one of the self- fertilised plants 

 having grown to an unusual height. All four crossed plants 

 flowered before their self-fertilised opponents. The cross- 

 fertilised flowers on the parent-plants in comparison with the 

 self-fertilised flowers yielded seeds in the proportion of 100 to 60. 

 So that here again we may draw the same conclusion as in the 

 two last cases. 



(10.) Passiflora gracilis.Oaly two crossed and two self- 

 fertilised plants were raised ; and the former were to the latter in 

 height as 100 to 104. On the other hand, fruits from the cross- 

 fertilised flowers on the parent-plants contained seeds in number, 

 compared with those from the self-fertilised flowers, in the pro- 

 portion of 100 to 85. 



(11.) I'haseolus multiflorus. The five crossed plants \vere to 

 the five self-fertilised in height as 100 to 96. Although the 

 crossed plants were thus only four per cent, taller than the 



