236 FERTILIZATION OR FECUNDATION. 



pollen, which is discharged by the dehiscence of the anther. The 

 pistil, or the female organ, is provided with a secreting surface or 

 stigma, to which the pollen is applied in order that the ovules con- 

 tained in the ovary may be fertilized. 



489. The existence of separate sexes in plants appears to have been 

 conjectured in early times, as shown by the means taken for perfecting 

 the fruit of the Date Palm. In this palm, the stamens and pistils are 

 on separate plants; and the Egyptians were in the habit of applying 

 the sterile flowers to those in whicn the rudiments of the fruit appeared, 

 in order that perfect dates might be produced. This practice appears 

 to have been empirical, and not founded on correct notions as to the 

 parts of the plant concerned in the process. In the case of the Fig, 

 they were in the habit of bringing wild figs in contact with the culti- 

 vated ones, on the erroneous supposition that a similar result was pro- 

 duced as in the case of the Date, proving that they were not aware of 

 the fact, that in the Fig there are stamens and pistils present on the 

 same receptacle. The effect produced by the wild figs, or the process 

 of caprification (caprificus, a wild fig-tree), as it was called, seems to 

 depend on the presence of a species of Cynips, which punctures the 

 fruit, and causes an acceleration in ripening. The presence of sexual 

 organs in plants was first shown in 1676, by Sir Thomas Millington, 

 and it was afterwards confirmed by Grew, Malpighi, and Ray. Lin- 

 naeus made it the basis of his artificial system of classification. 



490. Numerous proofs have been given of the functions of the sta- 

 mens and pistils, especially in the case of plants where these organs are 

 in separate flowers, either on the same or on different plants. Thus, a 

 pistilliferous specimen of Palm (Chamaerops humilis), in the Leyden 

 Botanic Garden, which had long been unproductive, was made to pro- 

 duce fruit by shaking over it the pollen from a staminiferous specimen. 

 The same experiment has on several occasions been performed in the 

 Botanic Garden at Edinburgh, and the fruit thus ripened has furnished 

 seeds which have germinated. Similar results were observed in the 

 case of the Pitcher plant. In Cucumbers, when the staminiferous 

 flowers are removed, no perfect fruit is formed. Removing the sta- 

 mens in the very early state of the flower, before the pollen is perfectly 

 formed, prevents fertilization. Care must be taken, in all such experi- 

 ments, that pollen is not wafted to the pistil from other plants in the 

 neighbourhood, and the result must be put to the test by the germina- 

 tion of the seed; in some instances, the fruit enlarges independently of 

 the application of the pollen, without, however, containing perfect seed. 

 Thus, a species of Carica was fertilized by the application of pollen, and 

 produced perfect fruit and seed, and it continued for at least one year 

 afterwards to have large and apparently perfect fruit, but the ovules 

 were abortive. 



491. Some authors maintain, that in the case of Hemp, Lychnis 



