LIFE HISTORIES OF FAMILIAR PLANTS 



I then pointed out how the male and female 

 catkins grew apart, so that the wind might effect 

 cross-pollination by blowing the pollen from 

 the male catkins to the stigmas of the female. 

 Now we see in the case of the willows this 

 device has been carried much farther ; their 

 catkins grow on distinct trees, so that not only 

 is cross-pollination effected, but it becomes im- 

 possible for the female flowers to be fertilised from 

 the pollen of male flowers growing on the same 

 tree. Thus a still more perfect cross-fertilisation 

 is eventually brought about. 



I have previously mentioned that at the 

 base of the stamens in each male flower there is a 

 tiny gland ; also at the base of the ovary in each 

 female flower is found a similar organ. These 

 glands produce very profusely a colourless honey 

 or nectar ; and the honey smell is very strong 

 when the flowers are maturing. Consequently, 

 numerous honey and wild bees are continually 

 visiting the flowers throughout the day, becoming 

 more or less covered with yellow pollen from the 

 stamens of the male catkins ; and this they convey 

 to the female stigmas on distant trees. Also, this 

 same sweet smell of the honey attracts numerous 

 species of moths by night ; indeed, visiting the 

 sallow blooms with lantern and " killing-bottle" is 

 a very profitable occupation for the entomologist 

 during spring nights ; the moths likewise visit both 

 male and female trees. 



Now catkins are a form of inflorescence 

 specially adapted for wind-pollination. How 



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