MIMICRY. 303 



woods, the falling leaves of trees apparently become alive, and 

 creep upon the ground." * 



Our second illustration is from the pen of that keen and 

 excellent observer, Mr. Belt : — " I was much surprised with the 

 behaviour of a green leaf-like Locust. This insect stood im- 

 movably among a host of Ants, many of which ran over its legs 

 without ever discovering there was food within their reach. So 

 fixed was its instinctive knowledge that its safety depended on 

 its immovability, that it allowed me to pick it up and replace it 

 among the Ants without making a single effort to escape. This 

 species closely resembles a green leaf."t 



If we consider it unsafe to predicate the colours of animals 

 in past geological eras on the basis of their present hues and 

 markings, it is as equally unwarranted to conclude that the 

 nature of their food was the same then as now. And therefore 

 we must be prepared to admit that probably insects had enemies 

 in the past which are now only known as non-insectivorous, 

 and the same suggestion will apply to other animals. This line 

 of argument is prompted by the many recorded examples of wild 

 and domesticated animals who have taken to a food totally 

 different to that of other members of their family and even 

 genus. It is necessary to give some examples, for, if not over- 

 looked, such facts seem little taken into consideration. At the 

 same time only some among many instances can be quoted. 



Mammals. — Macacus cynomolgus, a well-known Monkey of 

 Malasia, according to Sir Arthur Phayre, frequents salt water 

 creeks and devours shell-fish, thus being known among naturalists 

 as "the Crab-eating Macaque." " A l'egard des jeunes oiseaux, 

 le gorille et le chimpanze font preuve d'une telle voracite qu'ils 

 avalent leur proie sans la deplumer." J Bonvalot narrates that 

 small Thibetan Horses " feed on raw flesh, as we have seen with 

 our own eyes."§ Sandeman, writing of South Africa, observes 

 that, though many of the Horses never get over their dislike to 



* Preface to the ' Museum Regis Adolphi Friderici,' transl. by Jas. Ewd. 

 Smith (1798). 



f ' The Naturalist in Nicaragua,' p. 19. 



I L. F. de Pauw, ' Bull. Soc. Anthrop. Bruxelles,' 1894, p. 140. 



§ ' Across Thibet,' vol. ii. p. 64. 



