EXERCISE 47 

 HOW ARE SEEDS AND FRUIT FORMED FROM THE PISTIL? 



Materials. Tomato flowers and fruits in all stages of develop- 

 ment, from the newly opened flower to the ripe fruit. The small 

 and unimproved varieties, as the cherry tomato, are much to be 

 preferred to the improved garden varieties. Many other fruits, as 

 ground cherry, wild nightshades, lemon, orange, apple, and pear, 

 may be used for this or similar studies. 



Directions for work. Make floral diagrams, both vertical and 

 transverse, showing the relative position of all the floral organs. 

 Include a cross section of the ovary in your diagrams or draw 

 it separately. 



Arrange the tomato fruits in order of age, judging by relative 

 size and general appearance. By studying them in succession 

 find out what becomes of each of the parts of the flower. Make 

 a series of two or more vertical diagrams showing these facts. 



Make cross sections of the fruits in different stages of de- 

 velopment and represent in diagrams the changes which take 

 place in the internal parts of the fruits. 



Write briefly the story of the development of the fruit from 

 the flower. 



Any other plant which bears flowers and fruits at the same 

 time may be used. Evening primrose and the peas and beans 

 are suggested. 



References 



BERGEN and CALDWELL. Practical Botany, pp. 111-114. 

 BERGEN and CALDWELL. Introduction to Botany, pp. 130-132. 



[59] 



