88 Animal Life and Intelligence. 



Mimicry is not confined to the invertebrates. A harm- 

 less snake, the eiger-eter of Dutch colonists at the Cape, 

 subsists mainly or entirely on eggs. The mouth is almost 

 or quite toothless ; but in the throat hard-tipped spines 

 project into the gullet from the vertebrae of the column in 

 this region. Here the egg is broken, and there is no fear 

 of losing the contents. Now, there is one species of this 

 snake that closely resembles the berg-adder. The head 

 has naturally the elongated form characteristic of the 

 harmless snakes. But when irritated, this egg-eater flattens 

 it out till it has the usual viperine shape of the *'club" 

 on a playing-card. It coils as if for a spring, erects its 

 head with every appearance of anger, hisses, and darts 

 forward as if to strike its fangs into its foe, in every way 

 imitating an enraged berg- adder. The snake is, however, 

 quite harmless and inoffensive.* 



Here we have mimicry both in form and habit. Another 

 case of imperfect but no doubt effectual mimicry is given 

 by Mr. W. Larden, in some notes from South America.f 

 Speaking of the rhea, or South American ostrich, he 

 says, " One day I came across an old cock in a nest that 

 it had made in the dry weeds and grass. Its wings and 

 feathers were loosely arranged, and looked not unlike a 

 heap of dried grass ; at any rate, the bird did not attract 

 my attention until I was close on him. The long neck was 

 stretched out close along the ground, the crest feathers 

 were flattened, and an appalling hiss greeted my approach. 

 It was a pardonable mistake if for a moment I thought 

 I had -come across a huge snake, and sprang back hastily 

 under this impression." 



Protective resemblance and mimicry have been con- 

 by Mr. W. L. Sclater, and given by Mr. E. B. Poulton, in his " Colours of 

 Animals" (p. 252), where a (probably) homopterous insect mimics a leaf-cutting 

 ant, together with its leafy burden — a membranous expansion in the mimic 

 closely resembling the piece of leaf carried by the particular kind of ant he 

 resembles. 



* The late Mr. H. W. Oakley first drew my attention to this snake. 

 Since then Mr. Hammond Tooke has described the facts in Nature, vol. xxxiv. 

 p. 547. 



t Nature, vol. xlii. p. 115. 



