124 Plants and their Ways in South Africa 



have not wholly revealed themselves until they are past 

 pressing. 



The pleasure in knowing a flower's structure and plan is 

 increased when we learn the meaning of the endless variety of 

 forms and markings from patient watching or from reading what 

 others found. Long after flowers had been studied and their 

 parts described the use of pollen remained a mystery. At 

 last, in 1682, an English botanist, Nehemiah Grew, discovered 

 that before seeds were produced pollen must be transferred 

 to the stigma. No one believed him, nor did he know just 

 why it was so. Fifty years later Linnaeus, the Swedish botanist, 

 said it was true, and then people began to think it must 

 be so. It is hard to believe what we do not understand. 

 Even the great Linnaeus had not found out all, and it was 

 thought that pollen was necessary for the ovules of the same 

 flower; since, in the Roella family, for instance, the pollen 

 from the anthers is all caught upon the bristles along the 

 style of the same flower. . But even here the pollen has been 

 brushed off before the clapper-like stigmas have split open at 

 the end and exposed the part which receives the pollen if it is 

 to be of service to that flower. One man declared even that 

 when a pollen grain had been caught on a bristle it drew back 

 and pulled the pollen grain into the style. It does not, but 

 when we have wrong ideas they make us think a great many 

 things are true that are not. He thought he saw what he was 

 so sure must happen. 



Another fifty years went by. People were carefully and 

 patiently watching, and the truth is bound to be known when 

 people are eager to know it. A German botanist, Sprengel, 

 found that in most flowers the pollen cannot reach the stigma 

 of its own flower, even if it is caught on the style, unless it 

 reaches the tip or sensitive part of the stigma. What he saw 

 puzzled him and others, until Darwin, seventy years later, 

 showed that nearly all flowers are so constructed that they 

 receive pollen from another flower, and so ovules are usually 

 cross fertilized. 



When pollen has been transferred from the stamens to a 

 pistil, the pistil has been pollinated. But that is not all, for 



