A NATURALIST IN BRAZIL 



common livery. Various species of Capricorns, Weevils and 

 Buprestidae have adopted the black and yellow signals, and many 

 forms endeavour, by the constriction and deportment of the body, 

 to imitate the dreaded sting-bearers. 



A very great number of flies and butterflies imitate wasps, bees 

 or hornets. In the case of the flies no extensive modifications of the 

 body are necessary to ensure deception ; they have, like their models, 

 transparent wings; only one pair, of course, whereas wasps and 

 bees have two pairs (Plate 29, II, 19, 15). Among the butterflies 

 the Burnet-moths already mentioned are shaped like the Wasps, 

 while another group, the Glasswings, have lost even the scales of 

 their wings, and fly from flower to flower on transparent pinions. 

 In these forms the likeness to the bees and wasps is often so great 

 that even the expert is continually deceived (Plate 29, I, 10, 11). 



Much more numerous, however, than the insects which imitate 

 other insects are those which imitate lifeless objects, or leaves, 

 twigs and flowers. The distance to be travelled is shorter; once a 

 protective coloration is assumed only a few steps have to be taken ; 

 the modifications of colour are followed by modifications of form. 

 Here again it is the insect world which affords innumerable examples 

 of such evolution, and once more they occur chiefly in the tropics, 

 where the greater wealth of forms oflfers greater scope. The insects 

 of Brazil, in particular, must amaze the attentive observer, who 

 suddenly recognizes as a living creature what at first appeared to 

 be a fragment of bark or a leaf. But he must, of course, keep his 

 eyes open. An American engineer with whom I spent some days 

 wandering through the mangrove-woods near Tamarande in 

 Pernambuco, and who astonished me by detecting, at a considerable 

 distance, an iguana amidst the branches of a lofty tree, told me 

 that he had trained himself to note movements only. Now he was 

 always aware of the very smallest movements. This I could under- 

 stand, for animals pay more attention to movements than to any- 

 thing else ; I often found that deer or foxes would come quite close 

 to me if I did not move, even if I were standing in an open meadow 

 or in the middle of a path. 



Let us now make a survey of the insect world, in order to realize 

 how far Nature has endowed certain groups with the arts of mimicry. 



Over the pond the dragonflies pass and repass with whirring 

 flight, now and again falling upon some insect, and eating it as 

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