THE COLOURS OF ANIMALS AND PLANTS 149 



Fruits. 



Fruits consist of seeds with surrounding envelopes 

 of various kinds, and require to disperse their seeds 

 so as to reach places favourable for growth and 

 germination. Dispersion of the seeds is effected in 

 some cases, such as the dandelion, by means of the 

 wind ; in the edible fruits, on the other hand, it is 

 effected by the fruit being swallowed by animals as 

 food. Fruits are divided into two great groups — 

 attractive fruits and protective fruits. 



Attractive Fruits are soft, pulpy, and agree- 

 able to the taste — such as the cherry, grape, straw- 

 berry, &c. — and are devoured by birds or mammals. 

 In these the seeds themselves are hard, and pass 

 through the animal unchanged. It is probable that 

 every brightly-coloured pulpy fruit serves as food 

 for some species of bird or mammal. 



Protective Fruits, such as nuts. In these 

 the part that would be eaten by an animal is the 

 seed itself, and this is protectively coloured, being 

 green while on the tree, and turning brown as it 

 ripens and falls to the ground. Many seeds are 

 specially protected, such as the chestnut by its prickly 

 coat, and the walnut by its nauseous covering. 



It thus appears that we owe the existence of many 

 flowers to insects, and of many fruits to birds and mam- 

 mals. This is an excellent example of the interest 

 imparted to everyday life by the theory of Natural 

 Selection, which tells us that we have merely to 

 watch closely, to note carefully what is going on 

 every day before our eyes, in order to obtain the 



