76 Mr John "Wilson on the Dimorpltism of [sess. h. 



distinct plants bore two seeds — average '28. Thirty-three 

 crosses were made between dissimilar flowers, and in twenty- 

 eight of them the pollen was taken from the anther of the 

 one flower which corresponded exactly in position with the 

 stigma of the other. Seventy-four seeds in all were borne 

 by the thirty-three flowers, that is, an average of 2'24 for 

 each flower. Three seeds is the full complement of the 

 capsule. The results in sections " Crossed" point directly to 

 the fact that what may be termed the intended cross is best. 

 In comparing the last two columns in the table, the relative 

 number of failures " and successes is remarkable. In the 

 " Likes" (same type) the numbers fall from 12 unfertilised, 

 through 6 bearing one seed, 1 bearing two seeds, to none 

 bearing three seeds ; whereas the " Unlikes " rise from 1 

 bearing no seed, through 7*8 and 17 bearing one, two, and 

 three seeds respectively. The nineteen flowers in the former 

 series bore only eight seeds in all ; whereas the thirty-three 

 flowers in the latter series bore seventy-four, the ratio being 

 as 100 to 532. These figures fulfil one's anticipations. The 

 presumption is that if an insect of sufficient spread of wings, 

 after having visited a flower of one type, alights on a flower 

 of the other, it must cross-fertilise the latter, inasmuch as 

 the stigma will come exactly in contact with the part of the 

 insect's wing bearing pollen from the former plant. And while 

 one cross is being effected, new pollen is being acquired for 

 pollination of the opposite type. The success, however, 

 indicated by the figures in the second column of the table 

 may well give rise to speculation. 



The seeds were all kept in separate packets for further 

 study; but, during winter, they unfortunately became mouldy, 

 and hence proljably deteriorated, a circumstance which led 

 to their Ijcing sown promiscuously. Twenty-eight germinated, 

 and are growing vigorously, a fact which leads one to infer 

 that a large percentage of the seeds saved must have been 

 good, and that, but for the partial damage they sustained, 

 some confinuiitioii of llie results of fertilisation might have 

 been drawn from their germination. 



The plants used in the expeiiments were gathered and 

 sent direct from Cape Colony by the writer's In'other, Mr 

 Alexander Wilson. 



[P./S'. — Since the aljove was read, additional experiments 



