CHAPTER XII. 



DISTRIBUTION OF POLLEN BY THE WIND AND BY INSECTS 

 SELF AND CROSS FERTILISATION DICHOGAMY 

 PLANTAGO SILENE DOG-DAISY OR CHRYSANTHEMUM 

 LEUCANTHEMUM. 



OF the flowers which form the subject of the present 

 chapter, two, namely Silene and the dog-daisy (Chrysan- 

 themum), are visited by insects, and the distribution of 

 the pollen is carried on by their agency. In the remaining 

 flower, the plantain (Plantago lanceolata), the pollen is 

 carried by the wind. A number of other plants are in the 

 same case, for instance fir trees, the yew, hazel, oak and the 

 great class of grasses : such plants have certain characters 

 in common, which may be demonstrated on the plantain. 

 The " heads " of the plantain are made up of a number of 

 minute flowers massed together, each flower consisting of 

 four simple sepals, and a tubular corolla of four mem- 

 branous brown petals. 



Here we have one of the chief characteristics of wind- 

 fertilised plants, namely that the flowers are small, simple, 

 and inconspicuous, presenting a striking contrast to the 

 brightly coloured petals of insect-fertilised flowers. The 



