90 THE STOKY OF THE PLANTS. 



them altogether. But they are very useful for 

 all that, as we may easily guess, because they 

 are found in almost all the most advanced and 

 developed flowers. The use of the corolla, with 

 its brilliantly coloured petals, is to attract insects 

 to the flowers and induce them to carry pollen 

 from plant to plant. That is why they are 

 painted red and blue and yellow ; they are there 

 as advertisements to tell the bee or butterfly, 

 "Here 'you can get good honey." The use of 

 the calyx is usually to cover up the flower in the 

 bud, to keep it safe from cold, and to protect it 

 from the attacks of insect enemies, who often 

 try to break through and steal the half-developed 

 pollen in the bags of the stamens before it is 

 ripe and ready for fertilising. These are the 

 chief uses of the calyx or outer cup of the 

 flower ; but, as we shall see hereafter, it serves 

 many other useful purposes from time to time 

 in various kinds of flowers. In the fuschia, for 

 example, it is quite as brilliantly coloured as the 

 petals of the corolla, and supplements them in 

 the work of attracting insects. In the winter 

 cherry or Cape gooseberry it forms a brilliant 

 outer envelope or covering for the fruit, which 

 the French call "cerise en chemise" or "cherry 

 in its nightdress." Other uses of both calyx 

 and corolla will come out by and by, as we 

 proceed to examine individual instances. 



" But why," you may ask, " do the plants 

 want to get pollen carried from plant to plant ? 

 Why can't each' flower fertilise itself by letting its 

 pollen fall upon its own pistil ? " Well, the ques- 

 tion is a natural one ; and, indeed, many flowers 



