The Making of Species 



species imitated are " even more unpalatable than 

 the generality of their order." 



3. It is pointed out that the most distasteful 

 groups of butterflies the Danaidce, the Acrceincz, 

 the Ithomiince, and the Heliconincz consist of 

 large numbers of species which closely resemble 

 one another. This is said to be due to Mlillerian 

 mimicry. Mayer states that in South America 

 there are 450 species of inedible Ithomiincz which 

 display only 15 distinct colours, while the 200 

 species of Papilio, which are edible, exhibit 36 

 distinct colours. Nevertheless, he says, there is 

 no lack of individual variability among the former 

 hence their conservatism as regards colour cannot 

 be attributed to their having but little tendency 

 to vary. 



4. It is asserted that although in many cases 

 the mimetic resemblances extend to the minutest 

 detail, nevertheless they are not accompanied by 

 any changes in the mimetic species except such 

 as assist in the production or strengthening of a 

 superficial likeness. 



Pictures illustrating such cases of mimicry are 

 figured on pp. 241, 247, and 251 of Wallace's 

 Darwinism (1890 edition). 



5. It is stated that mimetic resemblance is not 

 confined to colour, but extends to pattern, form, 

 attitude, and movement ; that deep-seated organs 

 are affected when the superficial resemblance is 

 intensified, but not otherwise. Poulton cites 



228 



