88 LIN ARIA VULGARIS. CHAP. III. 



after a time the crossed seedlings slightly exceeded the self- 

 fertilised in height. When a little further grown, the longest 

 leaves on the former were very nearly 3 inches in length, 

 whilst those on the self-fertilised plants were only 2 inches. 

 Owing to an accident, and to the pot being too small, only one 

 plant on each side grew up and flowered ; the crossed plant was 

 19s inches in height, and the self-fertilised one 15 inches; or as 

 100 to 77. 



LlNARIA VULGARIS. 



It has been mentioned in the introductory chapter that two 

 large beds of this plant were raised by me many years ago from 

 crossed and self-fertilised seeds, and that there was a conspicu- 

 ous difference in height and general appearance between the 

 two lots. The trial was afterwards repeated with more care ; 

 but as this was one of the first plants experimented on, my 

 usual method was not followed. Seeds were taken from wild 

 plants growing in this neighbourhood and sown in poor soil in 

 my garden. Five plants were covered with a net, the others 

 being left exposed to the bees, which incessantly visit the flowers 

 of this species, and which, according to H. Miiller, are the 

 exclusive fertilisers. This excellent observer remarks * that, as 

 the stigma lies between the anthers and is mature at the same 

 time with them, self-fertilisation is possible. But so few seeds 

 are produced by protected plants, that the pollen and stigma of 

 the same flower seem to have little power of mutual interaction. 

 The exposed plants bore numerous capsules forming solid 

 spikes. Five of these capsules were examined and appeared to 

 contain an equal number of seeds; and these being counted in 

 one capsule, were found to be 166. The five protected plants pro- 

 duced altogether only twenty-five capsules, of which five were 

 much finer than all the others, and these contained an average of 

 23 6 seeds, with a maximum in one capsule of fifty-five. So that 

 the number of seeds in the capsules on the exposed plants to 

 the average number in the finest capsules on the protected 

 plants was as 100 to 14. 



Some of the spontaneously self-fertilised seeds from under 

 the net, and some seeds from the uncovered plants naturally 

 fertilised and almost certainly intercrossed by the bees, were 

 sown separately in two large pots of the same size ; so that the 



Die Befruohtung,' &c. p. 279. 



