FRUITS 



57 



It becomes very evident after we have studied a number of 

 flowers and have then taken up the fruits, that the same part of 

 the flower almost invariably appears as a certain part of the 

 fruit, although the part may serve a very different purpose in the 

 different fruits. We have already referred to some examples of 

 this. Take as another example the fate of the ovary wall or 

 pericarp in such fruits as the peach, the apple, the pea, the nut, 

 and a key fruit of maple. In all the above the pericarp of one 



Young cedars around parent tree. Photographed by Overton. 



is homologous with the pericarp in another. Yet what a contrast 

 between the papery core of the apple and the hard shell of the 

 nut, the partly fleshy and partly hard pericarp of the peach and 

 the outgrowth we call the wing of the key fruit. ^ 



Seed Dispersal.^ — If you will go out any fall afternoon into 

 the fields, a city park, or even a vacant lot, you can hardly 

 escape seeing how seeds are scattered by the parent plants 

 and trees. If you count the young maple seedlings which 



^ The teacher should point out other homologies in flowers and fruits. This 

 field is one of the richest in this respect in all the field of botany and zoology. 



2 At this point a field trip may well be taken with a view to finding out how 

 the common fall weeds scatter their seeds. Fruits and seeds obtained upon this 

 trip will naake a basis for laboratory work on the adaptations of seed and fruit 

 for dispersal. 



