A NATURALIST IN BRAZIL 



at the centre of the leaf, which is slightly dished, as though it had 

 warped on withering. Anyone who examined the detached wing of 

 such a Leaf-locust would infallibly take it to be an actual leaf, 

 even after close examination. But once the insect takes to flight it 

 displays, on unfurling its silvery, glistening hind-wings, the identifica- 

 tion-marks of its species. One species has the hind-wings streaked 

 with brown, and on each wing is a large, beautiful eye, like the eye 

 of a peacock-feather (Plate 29, II, 2). 



Some of the Praying Mantises bear an astonishing resemblance 

 to green leaves. These are locusts whose fore-legs are held up as 

 though in prayer, though their actual function is to catch other 

 insects, which are held as in a vice by the hinged legs, and then 

 devoured at ease (Plate 29, II, i). 



For strangeness of form, the Stick-insect may be ranked with the 

 Leaf-insect (Plate 29, II, 16). These insects, which grow to a length 

 of 8 inches and more, have thin, rounded bodies, and resemble 

 a twig so exactly that even Wallace could not believe that he was 

 looking at an insect when a native brought him one of these curious 

 creatures. The Stick-insects, moreover, instinctively keep their legs 

 pressed close against their bodies, and stretch out their fore-legs 

 before them, still further prolonging the twig-like body. Their 

 mimicry is so painstaking that where the fore-legs run under the 

 head a recess is formed to admit the head, so that no prominence 

 breaks the outline of the apparent twig (16). But many of the 

 Stick-insects find that even this disguise is not enough ! If in spite 

 of it they are detected by an enemy, they eject a spray of an acrid, 

 burning fluid, which is said to possess so intolerable a stench that 

 one cannot go near the insect. 



Unpleasant odours have been evolved as a means of defence by 

 still another order of insects : the Bugs. Their stinking exudation is 

 really an excellent means of intimidation, for if anyone eating 

 raspberries ever puts one of these insects into his mouth he will 

 pick the berries with twofold care thereafter, and will avoid even 

 touching such Tree-bugs. With such a means of defence, the insects 

 can safely permit themselves the most brilliant recognition-marks, 

 and as a matter of fact the bugs of Brazil, and especially the Shield- 

 bugs and Leather-bugs, are most beautiful insects, whose bodies 

 often gleam with a splendid metallic lustre (Plate 29, II, 4). There 

 are also bugs which protect themselves by their mimicry of bark. 

 It is almost impossible to detect such a Bark-bug when it is adhering 

 to the bark of a tree (Plate 29, II, 3). The body is so flat that it 

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