Page:The Zoologist, 4th series, vol 3 (1899).djvu/329

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MIMICRY.
303

woods, the falling leaves of trees apparently become alive, and creep upon the ground."[1]

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 immovably 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."[2]

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 overlooked, 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'égard des jeunes oiseaux, le gorille et le chimpanzé font preuve d'une telle voracité qu'ils avalent leur proie sans la déplumer."[3] Bonvalot narrates that small Thibetan Horses "feed on raw flesh, as we have seen with our own eyes."[4] Sandeman, writing of South Africa, observes that, though many of the Horses never get over their dislike to

  1. Preface to the 'Museum Regis Adolphi Friderici,' transl. by Jas. Ewd. Smith (1798).
  2. 'The Naturalist in Nicaragua,' p. 19.
  3. L.F. de Pauw, 'Bull. Soc. Anthrop. Bruxelles,' 1894, p. 140.
  4. 'Across Thibet,' vol. ii. p. 64.