262 The Great World's Farm 



which ripen in succession, and need constant examination. 

 These two dehcacies, their sole food, the ants are always 

 ready to defend, and during the wet season hundreds of 

 them may be seen running about on the young leaves, 

 which are thus kept clear of all enemies for some time 

 after they unfold. 



A very different ant, the parasol, or leaf-cutting ant, 

 is one of the worst enemies of vegetation in tropical 

 America, where it is called the curse of the country, 

 owing to the damage which it inflicts on the crops. It 

 may be a friend in disguise to the wild crops, by prevent- 

 ing their too great increase, and its services in the past in 

 burrowing and tunneling and in adding to the organic 

 matter of the soil must not be forgotten; but at the present 

 day the farmer can hardly look upon it as other than an 

 enemy. It is the cultivated plants of foreign origin which 

 it especially attacks, for very many of the natives are 

 protected against it in one way or other, while the foreign- 

 ers are undefended — a good example of the risks some- 

 times run in this way by colonists. 



The Indians defend their trees by a very simple device, 

 that of fastening thick wisps of grass with the sharp 

 points turned downwards round their stems. The multi- 

 tude of points quite baffles the ants, and prevents their 

 climbing farther up. Orange-growers plant their young 

 trees in the center of ring-shaped earthen vessels, which 

 are kept filled with water, and answer one of the purposes 

 of the natural "basins" of the teasel, and other similar 

 plants. 



In some parts of America orange-trees have run wild, 

 and have formed thickets, in spite of the ants; but gener- 

 ally speaking, all the species of the citron family — the 



