THE CAUSE OF MIMETIC KESEMBLAUCE ETC. 061 



a/Qi'mals are learning what to eat with impunity and what, to 

 reject. The paper was translated by Prof. E.. Meldola and pub- 

 lished in this country almost immediately after its appearance 

 (Proc. Eat. Soc. Loud. 1879, p. xx). 



The facts which the Miillerian theory sought to explain con- 

 cerned the fauna of tropical America ; the naturalist who ex- 

 plained them was a resident iu the same part of the world. A 

 few years later, however, F. Moore (Proc. Zool. Soc. 1883, p. 201) 

 showed that there is the same resemblance between the dominant 

 butterflies of the tropical East ; and last year I pointed out that 

 the same facts hold iu Africa (lieport of the British Association 

 at Toronto, 1897, pp. 688-691). See also Eoland Trimen's 

 Presidential Address to the Eutomoiogical Society, Jan. 19th, 

 1898 (Proceediugs, 1897, p. Ixvi). In the ' Proceedings ' of 

 the Eutomoiogical Society (1897, p. xsix), as well as in the 

 former paper (p. 691), 1 argued that such resemblance is not true 

 Mimicry at all, but rather an example of Common Warning 

 Colour, and with the assistance of Mr. Arthur Sidgwick I sug- 

 gested the term Si/naposematic as descriptive of it ; the term 

 Aposemaiic having been previously suggested for ordinary 

 Warning Colours (Poulton, Colours of Animals, Internat. Sci. 

 Ser., London, 1890, p. 8^7). 



I have now given a brief account of the leading phases in 

 the history of Mimicry. Even before the appearance of Eritz 

 Miiller's paper a great effect had been produced. This immediate 

 stimulus to tlie investigation of new examples and fresh aspects 

 of Mimicry which f ullowred Bates's memoir, must be ascribed to 

 the fact that then for the first time was offered a good working 

 hypothesis — a hypothesis which seemed to afford an adequate ex- 

 planation of one class of known facts, which challenged its critics 

 to find insuperable difficulties among facts as yet unknown. In 

 the thirty-six years which have elapsed since the appearance of 

 this great memoir an immense number of facts bearing upon the 

 subject have been discovered, and many naturalists consider that 

 Bates's theory of Mimicry as due to natural selection (sup- 

 plemented and completed by the kindred theory which we owe 

 to Fritz Miiller) has stood the test with complete success and is 

 in a far stronger position than in 1862. This opinion is more 

 generally held among the students of other groups of the animal 

 kingdom than among those who are specially devoted to entomo- 

 logy, but a considerable proportion of the latter also hold it firmly. 



