232 TYPICAL FRUITS 



Reference work (1) Do fruits require sunlight in order 

 to ripen? 



Pick two of each sort of several unripe fruits. Place one 

 of each in a dark place and the other where it will receive 

 the sunlight. Temperature and other conditions must be 

 the same for both samples. 



After a week's time, examine both fruits and note the 

 difference. 



(2) Do fruits require air in order to ripen ? 



Repeat the foregoing experiment, using fruits, some of 

 which have been previously coated with vaseline to close 

 the pores in their skins. 



(3) What is the function of the fruit skin or epicarp ? 

 Compare peeled with whole fruits both ripe and unripe. 



Does the removal of the skin have any effect on ripening ? 

 On retention of sap ? On hastening or retarding decay ? 



(4) Examine fruit skins with a microscope. Do they pos- 

 sess stomata? 



Query. Why do gardeners often pluck unripe tomatoes 

 and lay them where the sun shines to ripen? 



