260 THE COLOURS OF ANIMALS 



Experimental proofs of the protection afforded by 

 resemblance to serpents 



The success of this method of defence depends 

 upon an elaborate system of intimidation. An obvious 

 criticism suggests that this interpretation is too fanci- 

 ful, and that the appearance must have some other 

 meaning. It is therefore of the highest importance 

 to bring forward direct evidence proving that insect- 

 eating animals are actually terrified by such cater- 

 pillars. 



Professor Weismann offered a Large Elephant 

 caterpillar to a tame Jay, which immediately killed 

 and devoured it. His fowls were, however, much 

 awed by the appearance of a larva, although after 

 great deliberation one of them ventured to attack it, 

 when the imposition was of course instantly revealed, 

 and the caterpillar devoured. He then placed one in 

 the seed-trough, and found that the sparrows and 

 chaffinches were effectually kept off by it. One sparrow 

 flew down obliquely, so that the caterpillar was hidden 

 by the side of the trough until the bird was close upon 

 it ; the instant the caterpillar was seen, the bird clearly 

 showed its alarm by the sudden manner in which it 

 altered its course. 1 Lady Verney also found that small 

 birds would not come near a tray containing bread- 

 crumbs when one of these caterpillars was placed 

 upon it. 2 



1 Loc. cit. pp. 330-33. Good Wards, 1877, p. 833. 



