32 



STOVE PLANTS. 



it will of course occupy some time, but the greater quantity 

 of seed thus obtained will amply repay the extra trouble. 

 That this is so, we have had some striking proofs in the 

 course of some experiments we have made in reference to 

 this question. For example, we found that the stigma of 

 one flower fertilised with pollen from a separate flower, but 

 growing upon the same plant, yielded four times as much 

 as when left to fertilise itself, and above one-half more than 

 when artificially impregnated with its own pollen. Carrying 

 the experiment still further, and bringing pollen from another 

 plant of the same species, but which had not originally 

 sprang from the same stock, we found that the produce was 

 three times the quantity yielded under the most favourable 

 circumstances of the other experiment, viz., the fertilisation 

 by pollen from a separate flower of the same plant. The 

 contrast was, however, greatest with the flower which received 

 no aid whatever ; for with the foreign pollen applied artificially, 

 the yield of seed was finer in quality, and twelve times as 

 much in quantity, while in the respective cases of fertilisation 

 with foreign pollen (that is, pollen from a different plant), 

 and with its own pollen, the yield was five times greater in 

 favour of the foreign pollen. This will be seen more clearly 

 by the following table : — 



