BERRIES AND BERRIES. 93 



ferent parts among the various species. In 

 the plum it is the outer covering of the true 

 fruit which grows soft and coloured : in the 

 apple it is a swollen mass of the fruit-stalk 

 surrounding the ovules : in the rose-hip it is 

 the hollowed receptacle : and in the straw- 

 berry it is the same receptacle, bulging out in 

 the opposite direction. Such a general ten- 

 dency to display colour and collect sugary 

 juices in so many diverse parts may be com- 

 pared to the general bulbous tendency of the 

 tiger-lily or the onion, and to the general 

 succulent tendency of the cactus or the house- 

 leek. In each case, the plant benefits by it 

 in one form or another ; and whichever form 

 happens to get the start in any particular 

 instance is increased and developed by natural 

 selection, just as favourable varieties of fruits 

 or flowers are increased and developed in 

 cultivated species by our own gardeners. 



Sweet juices and bright colours, however, 

 could be of no use to a plant till there were 

 eyes to see and tongues to taste them. A 



