EXERCISE 105 

 POLLINATION 

 Materials. Flower of lily, or other large flower. 



Directions for work. Touch with a camel' s-hair brush an 

 anther which is shedding pollen, and then bring the brush into 

 contact with a stigma on which no pollen is visible. Examine 

 the stigma after touching with the brush. Do you find any 

 evidence that pollen can be transferred by this means? How 

 may the lily be pollinated in nature ? 



Examine stigmas in flowers of different ages, noting whether 

 there is anything in the condition of the stigma at any time 

 that favors the adherence of the pollen. If such a condition is 

 found, does it occur at the time the anthers in the same flower 

 are shedding pollen, before shedding, or after? How would 

 this affect the possibility of self-pollination ? 



Make a similar examination of flowers of several different 

 kinds with reference to the relation between the time of shedding 

 pollen and the condition of the stigma. 



References 



BERGEN and CALDWELL. Practical Botany, pp. 325, 326, chap. viii. 

 BERGEN and CALDWELL. Introduction to Botany, pp. 300, 301, chap. x. 



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