REVIEW OF PLANTS STUDIED 93 



a hard rind and a soft flesh within. In the apple, pear, 

 and quince, the enlarged calyx tube forms the edible part. 

 On the side opposite the stem the lobes of the calyx can 

 still be seen in the ripe fruit. In the Stone fruits, the outer 

 part of the ovary has become fleshy and the inner part 

 hard and stony. What other varieties of fruits have you 

 observed ? (See Gray : " Lessons in Botany.") It is very 

 important to the life of plants that their seeds should 

 not all remain near the parent plant. Often they could 

 not grow there at all, and if they were not carried to 

 other places, the species would be in danger of becoming 

 extinct. When we studied the common road weeds, we 

 learned that small seeds are often carried for miles by the 

 wind and also by water. You have noticed that nearly all 

 berries, when ripe, change their color from an inconspicu- 

 ous green to a conspicuous red, black, blue, yellow, or 

 white. Generally the taste also changes from sour to sweet. 

 The conspicuous color enables birds to find the berries, and 

 the sweetness makes them palatable. The hard seeds in 

 the berries pass through the bird without being digested, 

 and grow if they happen to be dropped in a suitable place. 

 Can you think of other contrivances by which plants dis- 

 seminate their seeds ? 



