134 IN THE GUIANA FOREST. 



happy family," but we could hardly agree with him 

 if he meant that they dwelt at peace with each 

 other. To us it brought up the great problem of 

 the dependence of plants on the natural elements, 

 of animals on plants, and these again on other 

 animals. By means of the soil, water, air, and 

 light, the forest tree rose beside the creek, and up 

 it had grown the elegant bignonia, whose flowers 

 were hanging so gracefully far overhead, and whose 

 stems stretched like cords from base to summit. 

 On a fork of the tree, and among the bush-ropes, 

 the orchid had found a congenial habitat, where it 

 grew and flourished for years, developing a great 

 mass of roots to be occupied by the immense horde 

 of ants. The plant might perhaps have lived with- 

 out such tenants, but it is most probable that its 

 flourishing condition was mainly due to these little 

 creatures. For, they were there with consent, and 

 in return for house accommodation undertook to 

 keep off the enemies of the orchid, of which the 

 cockroach was one of the most inveterate. Why, 

 then, were these pests allowed to be present ? We 

 can only suppose that the attraction of the plant 

 drew them, and that they had not yet been cap- 

 tured. For it is not to be supposed that even 

 this omnivorous insect will be deterred from 

 attempting to get a delicious meal simply because 



