EXERCISE 53 (Continued) 



is concerned, in quiet air ? Is the wing of any advantage, and, if 

 so, what advantage, when the wind is blowing ? 



Try the above experiments with several kinds of seeds to see 

 whether your conclusions are true of all. Compare several kinds 

 by dropping simultaneously. On the basis of your experiments, 

 what do you conclude to be the advantage of the possession of 

 a wing, and which of the seeds studied is best equipped in this 

 particular? Test your conclusions by observing seeds falling 

 from trees if possible. 



2. /Structure of wing. Examine and describe the wings. Note 

 shape, thickness, width, length, and relative weight. Can you 

 discover anything in the form and structure of different wings 

 that accounts for the peculiarities of their action ? 



Write a description of the several winged seeds and fruits 

 and illustrate with drawings which show the important features. 



References 



BERGEN and CALDWELL. Practical Botany, pp. 146-155. 

 BERGEN and CALDWELL. Introduction to Botany, pp. 166-171. 



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