234 THEORIES OF MIMICRY 



No theory except Natural Selection explains why the 

 number of colours and patterns in the dominant groups 

 of butterflies mentioned above are so few in relation to 

 the number of species, as was pointed out by Professor 

 Meldola, F.R.S., in his paper- Mimicry between Butter- 

 flies of Protected Genera?- These colours and patterns 

 have been recently studied very carefully, especially in 

 the Ithomiinae, by A. G. Mayer, 2 who shows that ' the 

 200 species of Papilio in South America display 36 

 distinct colors, while the 450 species of Danaoid Heli- 

 conidae \Ithomiinae\ exhibit only 1 5. Hence the numbers 

 of the species and of the colors are almost in inverse ratio 

 in the two groups. This may be explained by the fact, 

 that the Danaoid Heliconidae mimic one another, while 

 the Papilios do not. . . . There is no lack of individual 

 variability among the species of the Danaoid Heliconidae; 

 yet the species as a whole vary but little from the two 

 great types of color-pattern represented by Melinaea and 

 Ithomia. In order to account for this remarkable fact 

 I am forced to resort to Fritz Midler's theory of mimicry.' 3 

 Again, on page 225 Mayer remarks : 'It is difficult to 

 account for the remarkable conservatism in respect to 

 color- variations among the Heliconidae [here used, as in 

 Bates's original paper, to include Danainae, Ithomiinae, 

 and Heliconinae], unless we resort to the explanation 

 afforded by the theory of mimicry; for, while there is 

 such remarkable simplicity and uniformity of color- 

 pattern throughout the whole group of the Heliconidae 

 individual variations are very common.' 



It is not from any predisposition or bias in favour of 

 Natural Selection that these conclusions are reached, but 

 simply because this theory offers an explanation of so 

 many remarkable facts which are utterly meaningless 

 under any other theory yet brought forward. 



1 Ann. and Mag. Nat. Hist., 5th sen, vol. x, Dec. 1882, p. 417. 



2 Bulletin of the Mus. of Comp. Zool. at Harvard Coll., Feb. 1897, 

 p. 167. 



3 I.e. p. 229. 



