NATURALIST IN BRAZIL 



have called it the sea-cow; it is better known as the Manatee 



or Dugong. There is also a real fish, the Tambaqui, which 



grazes on the Eichhornia, and even eats the flowers of the 

 Victoria regia. 



We have hitherto regarded this ordered scheme of Nature only 

 as it benefits the eaters. But since Nature is a harmonious whole, 

 no animal and no plant is especially favoured, but each is so con- 

 ditioned as is best for the continuance of its species. And as the 

 animals, birds and insects need the plants, that they may live on 

 them, so conversely the plants need the animals, birds and insects. 

 For a plant, if it had no creatures to eat it, would multiply unchecked, 

 and would finally be stifled by the very excess of its own shoots or 

 saplings. In a sense the insects are gardeners, who prune the plants 

 to prevent them from running to leaves. And inasmuch as they 

 prevent every plant from spreading too vigorously, they keep it in 

 its proper place, and the other species of plants are able to grow 

 beside it. 



Provision, however, is made to ensure that this pruning is kept 

 within the proper limits. The insects themselves must not multiply 

 so excessively as to devour these food-plants entirely, for then they 

 would perish for want of the only form of nourishment which agrees 

 with them. Nature achieves this regulation by ensuring that every 

 insect, and indeed every animal, has it enemies, which keep it 

 within the necessary bounds by devouring the surplus of the race. 

 But in order that things may not be left to chance, when great 

 numbers of insects would be swept away, while others would be 

 hardly touched, the hunters too have been specialized, and each 

 species has its enemies, who are precisely adapted to its special 

 peculiarities. 



Thus, there are birds which catch creeping insects, and others 

 which snap up flying insects. If in Europe the early summer is cold 

 and rainy, most of the young swallows and fly-catchers perish, for 

 the insects do not fly in cold rainy weather, and we then regret that 

 these delightful little birds cannot eat worms and caterpillars instead. 

 But once more we must take the broad view, that the flying insects 

 must have their enemies, and that these, under normal circum- 

 stances, have more than enough to eat. 



In Brazil, where there is no winter, the insects are able to fly 

 all the year through, and so we find in Brazil an unusual number 



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