22 THE PHYSIOGNOMY AND PHYSIOLOGY 



It ^vas found that unless the pollen could by 

 some means be conveyed from the stamen- 

 bearing flowers to those Avhich contained pistils 

 and young fruit, the latter Avould never ripen, 

 but, after they had reached a small size, would 

 invariably wither and fall off. It was evident, 

 therefore, that the contact of the pollen was 

 necessary for maturing the fruit. The know- 

 ledge of this fact led to a wider investigation 

 of the subject, and it was found to apply 

 universally. In most plants, the stamens and 

 pistils are both in the same flower, so that when 

 the anthers discharge their pollen, a portion is 

 sure to fall upon the pistil; but in some the 

 stamens and pistils are in separate flowers. If 

 both kinds of flowers gi'ow on the same plant it 

 is termed momvcions ; but if stamen-bearing 

 oT male flowers grow on one plant, and pis- 

 tilliferous or female flowers on another and 

 distinct plant, it is then termed dioecious. This 

 is precisely the case with some of the palms, 

 among which is the date palm. Insects, flitting 

 from flower to flower, or the agency of the 

 winds, are usual means by wliich pollen is 

 conveyed from one flower to another in diajeious 

 plants ; but often there are no male palms 

 growing within a considerable distance of the 

 fruit-bearing ones, and the Ai-abs have, there- 



