226 TYPICAL FRUITS 



Suggestion. Compare the tomato with the grape, goose- 

 berry, and currant, which are typical berries; also with the 

 orange, melon, etc., which are modified berries. 



194. DEHISCENT FRUITS 



Object. To learn what is meant by dry fruits, and 

 how they scatter their seeds. 



Apparatus. Pods of beans, peas, locust, honey locust, catalpa, 

 or any other dry dehiscent fruit. 



Method. Study the fruits selected and determine how 

 they split. Some open on one seam only, others on two 

 seams, and still others in three or more places. 



Examine several old pods which have split and note 

 whether they are still flat or twisted. 



Do you see any advantage in having the valves twist as 

 they spring apart? 



Hang up several ripe pods not yet open and let them re- 

 main for some time. When they split, note the result. 

 What becomes of the seeds ? 



Conclusion. State what a dry fruit is and how the seeds 

 are scattered. 



195. SEED DISPERSAL 



Object. To learn some ways in which a plant scat- 

 ters its seeds. 



Apparatus. Maple keys, balsam or jewelweed plants in fruit, 

 and burdock or clotburs, desmodium, and milkweed. 



Method. (a) Study the maple key to get an idea of 

 the formation of its wing and the number of seeds it contains. 

 Throw one into the air and see how long it takes to fall to 

 the ground. Of what use is the wing? Compare it with 

 dandelion, milkweed, and ailanthus fruits. 



