Mimetic Attraction. 325 



nothing but the mimic ; while in the latter case (Miillerian 

 mimicry) the mimetic attraction is unlimited and mutual, 

 acting reciprocally in both directions and influencing each 

 member of the group. 



This doctrine of the mutual attraction between inedible 

 forms, leading not merely to the copying of one by 

 another, but to the departure of each from its original 

 aspect by the adoption of features belonging to the other, 

 is not simply a speculation, nor does it rest only on 

 a priori reasoning. There is much evidence that 

 it represents a fact which does actually take place in 

 nature ; and in the two papers above referred to* I have 

 brought forward cases which seem inexplicable by any 

 other principle. I may be allowed to add in this place a 

 further instance, which appears to me for several reasons 

 remarkable. 



The instance of P. locusta $ . In Trans. Ent. Soc. 

 Lond. 1896, p. 72, note, I spoke, though somewhat 

 doubtfully, of P. locusta ^ as a mimic. My suspicion 

 that this was the case at that time fell short of actual 

 conviction. Now, however, after a further careful 

 examination of P. locusta $ from this particular point 

 of view, I have little or no hesitation in pronouncing it to 

 be a member of a mimetic association of an exceptionally 

 interesting kind. 



It will be remembered that the males of Mylothris 

 lorena, M. pyrrha, etc., form a good illustration of the 

 accurate manner in which the appropriate habits are 

 correlated with adaptive colouring — the mimetic pattern 

 in these instances being confined to the underside, and 

 being in all probability useless as a protection except 

 during the resting position ; while the habits of these males, 

 as testified to by Wallace,t are such as would probably 

 render a Heliconiine resemblance during flight a source of 

 danger to its possessors rather than of safety. Similarly 

 in P. locusta ^ , it is only on the underside that the 

 mimetic pattern appears, and here again there can be 



*-■ See also an abstract in " British A.ssociation Reports," 1894, 

 p. 692. 



t "Tropical Nature," 1878, p. 205. See also Haase, op. cit., 

 p. 68. It should, however, be stated that neither of these authors 

 assigus any protective value to the underside of the male forms in 

 question. 



