EXERCISE 56 

 DISPERSAL OF SEEDS OF FLESHY FRUITS 



Materials. Fleshy, edible fruits of several kipds, such as apple, 

 pear, raspberry, strawberry, mulberry, and many fruits of wild 

 plants. 



Directions for work. Seeds of fleshy fruits are commonly dis- 

 tributed by being eaten along with the pulp and later voided 

 uninjured from the body of the animal. Birds are particularly 

 notable as distributors of seeds in this manner. 



What are the features of the fruits you are studying which 

 might attract the attention of animals and cause them to eat 

 the fruit? Note color, odor, and flavor. 



What characteristics, such as small size of the seeds and 

 intimate relation to pulp, make it extremely probable that the 

 seeds will be swallowed along with the pulp ? . 



What characteristics of the seeds make it appear improb- 

 able that any large proportion will be destroyed by mastication, 

 by grinding in the gizzards of birds, or by the action of the 

 digestive juices ? 



Make observations in the field to determine which fruits are 

 readily eaten by birds. Find out also whether any plants of 

 these sorts may be found growing in places where their presence 

 is difficult to explain except on the supposition that seeds are 

 carried by birds. Look especially for plants growing in the 

 forks of trees or in knotholes, on thatched roofs and on old 

 stacks of decaying straw or hay, and along fences or other 

 places where birds are accustomed to perch. 



From your observation, do you find that this is a successful 

 means of dispersal ? 



References 



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

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



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