264 FERTILISATION OR FECUNDATION. 



5. — Functions of the Organs of Reproduction — Fertilisation or 

 Fecundation. 



The stamens and pistil are called the Essential Organs of flowering 

 plants, inasmuch as without them reproduction cannot be eifected. In 

 plants which do not flower, this function is performed either by special 

 organs, which have been termed antheridia and archegonia, or it is 

 accomplished by a process of conjugation or union of cells. The stamens, 

 considered as the male organs, prepare the pollen, which is discharged 

 by the dehiscence of the anther. The pistil, or the female organ, is pro- 

 vided with a secreting surface or stigma, to which the pollen is applied 

 in order that the ovules contained in the ovary may be fertilised. 



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 which 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 cultivated ones, on the erroneous supposition that a similar 

 result was produced 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 MUlington, Savilian Professor at Oxford, and by Grew. 

 The opinions of these naturalists were subsequently confirmed by 

 Malpighi, Kay, Morland, Geoffrey, and others. Linnaeus made these 

 organs the basis of his artificial system of classification. 



Numerous proofs have been given of the functions of the stamens 

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

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

 pistilliferous specimen of Palm (Chamserops 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 



