58 TRAVELS ON THE AMAZON. [October, 



are constantly hopping about the bushes and twigs, picking off 

 whatever small insects they fall in with. 



The ant-thrushes are another closely allied group, which are 

 equally abundant. They have stronger legs and very short 

 tails, and walk more on the ground, picking up insects, espe- 

 cially ants, very much after the manner of poultry. "When one 

 is shot, it is often a dangerous matter to go and fetch it, for 

 the ground generally swarms with ants, which attack an 

 intruder most unmercifully both with stings and jaws. Many 

 times, after a fruitless attempt, have I been obliged to leave 

 the dead body on the field, and beat an inglorious retreat. 



In all works on Natural History, we constantly find details 

 of the marvellous adaptation of animals to their food, their 

 habits, and the localities in which they are found. But 

 naturalists are now beginning to look beyond this, and to see 

 that there must be some other principle regulating the infinitely 

 varied forms of animal life. It must strike every one, that 

 the numbers of birds and insects of different groups, having 

 scarcely any resemblance to each other, which yet feed on the 

 same food and inhabit the same localities, cannot have been 

 so differently constructed and adorned for that purpose alone. 

 Thus the goat-suckers, the swallows, the tyrant fly-catchers, and 

 the jacamars, all use the same kind of food, and procure it 

 in the same manner : they all capture insects on the wing, yet 

 how entirely different is the structure and the whole appearance 

 of these birds ! The swallows, with their powerful wings, are 

 almost entirely inhabitants of the air ; the goat-suckers, nearly 

 allied to them, but of a much weaker structure, and with 

 largely developed eyes, are semi-nocturnal birds, sometimes 

 flying in the evening in company with the swallows, but most 

 frequently settling on the ground, seizing their prey by short 

 flights from it, and then returning to the same spot. The 

 fly-catchers are strong-legged, but short-winged birds, which 

 can perch, but cannot fly with the ease of the swallows : they 

 generally seat themselves on a bare tree, and from it watch 

 for any insects which may come within reach of a short swoop, 

 and which their broad bills and wide gape enable them to 

 seize. But with the jacamars this is not the case : their bills 

 are long and pointed in fact, a weak kingfisher's bill yet 

 they have similar habits to the preceding : they sit on branches 

 in open parts of the forest, from thence flying after insects, 



