524 SEXUALITY OF VEGETABLES. CHAP. VI. 



tributing them to the accidental intermixture or 

 access of the pollen of a different species. Thus 

 Veronica spur la is thought to have sprung from 

 Veronica maritirna, impregnated by the pollen of 

 Verbena officinalis ; agreeing in its fructification 

 with the former, and in its leaves with the latter. 

 So also Delphinum hybridum is thought to have 

 sprung from Delphinum elatum and Aconitum Na- 

 pellus, by its combining together the features of 

 both. But this spurious" impregnation seems to be 

 confined within very narrow limits, and takes place 

 only among plants that are nearly related by natural 

 affinity. 



A. male Exper. 5. If a male plant is placed in the vici- 

 trodnced m ty f a female plant which, from its having been 

 or P? JJ e |^ formerly insulated, had produced no perfect seed ; 

 a distance, or if the pollen of a male plant of the same species 

 is conveyed to it from a distance and sprinkled over 

 the stigma, it will now produce perfect seed. A plant 

 of the DatiscaCannabina, which came up in the gar- 

 den of Linnaeus from seed about the year 1750, and 

 which produced afterwards many flowers, yielded 

 however no perfect seed, as the flowers happened to 

 be all female ; a few perfect seeds were now pro- 

 cured and sown with a view to raise some male 

 plants, but still they were all female. At last, 

 however, in 1757 a parcel of seed was procured, 

 from which a few male plants were obtained that 

 flowered in the following year. They were removed 

 to a distance from the females, and when their 



