12 PLANT LIFE. 



vegetables and corn, attempts have been made to do the 

 work of the bees or other insects artificially. The 

 result has been to prove that crossing is distinctly of 

 advantage. Pollen of one kind of wheat, for instance, 

 has been placed on the stigma of a different sort, and 

 the result has been to greatly increase the size and 

 yield of the ears. This has been done by Messrs. 

 Garton of Newton-le- Willows in Lancashire and Dr. 

 J. Wilson in this country, whilst in the United 

 States crossing of this kind is very largely practised. 

 Unsymmetrically coloured flowers, such as the Pansies 

 generally grown in our gardens, are probably due to 

 crossing carried out by insects. The dwarf Cannas 

 also are known to be the result of a cross with a 

 Costa Rican species. The remarkable increase in 

 size and weight found in some of the American dew- 

 berries when two varieties have been crossed is par- 

 ticularly worth noting. 



It is therefore quite clear that there is a decided 

 advantage in cross-breeding. There is also a danger 

 in continued inbreeding, and thus the insects hovering 

 over flowers or flying rapidly from one to another are 

 really in their service, and are greatly assisting in 

 securing the vigour of the future progeny. They are 

 paid for their trouble either by the pollen, part of 

 which they are allowed to devour, or by the honey 

 which flowers produce entirely for their benefit. 



The Whin is a very good example of a flower in- 

 tended to attract the more intelligent and industrious 

 sorts of insects, such as the humble bee. At first sight 

 there is no visible honey or pollen, as, in the younger 

 flowers, these are quite concealed. The honey, however, 

 will be found inside the base of the large uppermo.st 

 petal. In the flower of the sweet pea, pollen is left on 



