62 



HISTOUY OF THK VKGETABLE KINGDOM. 



hennaphrodite flower, or the stamen beai-ing 

 llowers of a monoecious plant are cut off before 

 Ihey shed their pollen, and care taken to pre- 

 vent the access of the pollen of any other plant 

 of the same species, the fruit wiU prove abor- 

 tive. From a flower of the red horned poppy 

 (chelidonum cormculaium) which was detached 

 from all other individuals of the same species, 

 Linnaeus removed all the anthers upon the first 

 opening of the blossom, and stripped off at the 

 same time aU the rest of the flowers ; but the 

 result of this experiment was that the flower 

 produced no seed. A gardener who cultivated 

 melons and cucumbers, but who was no botanist, 

 thinking that the stamenifcrous flowers of the 

 plant exhausted the nourishment due to the 

 other flowers, without being of any utility in 

 themselves, fancied that his plants would be 

 rendered more vigorous, his fruit of superior 

 flavour, and his profits consequently increased, 

 by means of tearing them off altogether. But 

 like the boy who cut open his goose that laid 

 golden eggs, in the hope of getting rich all at 

 once, he soon found cause to repent of his rash 

 experiment, for the consequence was that his 

 plants produced no fruit. If, after the anthers 

 have been removed, the poUen of another plant 

 of the same species be shaken over the pistil, 

 then the fruit will ripen as usual. Linneeus 

 proved this by first treating a flower of the 

 chelidonum corniculatum, as in the foregoing ex- 

 periment, and then sprinkling over the pistil 

 pollen brought from another plant of the same 

 species; when the flower produced perfect seeds. 

 Upon this principle, gardeners now assist the 

 impregnation, or what they call the setting of 

 the fruit, at least in the case of their melons and 

 cucumbers, by means of sprinkling the poUea 

 of the male flowers over the pistils of the females. 

 But if a plant has more than one pistil, and you 

 apply the pollen only to that one, then that 

 one only wiU ripen seed. 



If the stigma of the pistil is cut off before the 

 discharge of the pollen, no fecundation ensues, 

 and the fruit is inferior both in quantity and 

 quality. If, again, the stigma of a flower that 

 has been stripped of its stamens before the burst- 

 ing of the anthers is sprinkled with the poUen 

 of a plant of a different species, then the seeds 

 will not only ripen and produce perfect plants 

 when sown, but these plants will partake of the 

 qualities both of the fecundating and fecundated 

 species. The pollen of the tragopogon pratensis, 

 whose petals are yellow, when sprinkled on the 

 stigmas of the flower of the tragopogon purpureus, 

 whose petals are purple, yielded seeds that pro- 

 duced plants with both purple and yellow 

 flowers. Hence botanists account for the exist- 

 ence of what are called spurious plants, attribut- 

 ing them to the accidental mixture or access of 

 the pollen of a different species. Thus, veronica 



spuria is thought to have sprung from lerottica 

 tnaritima, impregnated by the poUcn of verbena 

 officinalis, agreeing in its fructification with the 

 former, and in its leaves with the latter. So 

 also delphinium hyhridum is thought to have 

 sprung from deJpMmum elatum and aconitum 

 najMllus, by its combining together the features 

 of both. But this spurious impreguation seems 

 to be confined within very naiTOw limits, and 

 takes place only among plants that ai'e nearly 

 related by natural affinity. 



If a male plant is placed in the neighbour- 

 hood of a female plant which from its having 

 been formerly insulated, had produced no per- 

 fect seed, 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 pro- 

 duce perfect seed. A plant of the datisca canna- 

 bina, which came up in the garden of Linnteus, 

 from seed about the year 1750, and which pro- 

 duced afterwards many flowere, yielded, however, 

 no perfect seed, as the flowers happened to be 

 all females. At last, however, in 1757, a parcel 

 of seed was procured, from which a few male 

 plants were obtained, that flowered in the follow- 

 ing year. They were removed to a distance from 

 the females, and when their flowers were ready 

 to discharge the pollen, It was collected by 

 means of shaking the panicle with the finger 

 over a piece of paper, tiU it was covered with a 

 fine yellow powder. The pollen thus obtained, 

 was immediately carried to the female plants, 

 which were growing in another part of the 

 garden, and sprinkled over them, in consequence 

 of which they now produced perfect seeds. But 

 the best example of this kind yet exhibited, is 

 that of the famous experiment of Linnteus upon 

 the Berlin and Leipsic palms. About the period 

 of the foregoing experiment, or rather a few 

 years prior to it, there grew at Berlin an indi- 

 vidual female palm tree which had never per- 

 fected any fruit, so as that no seeds would 

 germinate, while there grew at the same time, 

 at Leipsic, a male plant of the same species. 

 Hence it occurred to Linnteus, that the impreg- 

 nation of the female flowei-s of the fonner was 

 still practicable, even by means of the pollen 

 that might be procured, and carried from the 

 male flowers of the latter. Accordingly, a 

 flowering brancli of the male plant was dispatched 

 by post from Leipsic to Berlin, a distance of 

 twenty German miles, and shook or suspended 

 over the flowers of the female plant. The con- 

 sequence was, that the fruit was ripened, and the 

 embryo perfected, and young jjlants raised from 

 the seeds. Again, if the male plant be removed 

 from the vicinity of the female plant to which 

 it had given fecundity, the fruit of the female 

 plant is again produced imperfect as before. 

 About the year 1755, there grew in the garden 

 of M. de la Serrc, at Paris, a i'en;ale pistachio 



