[Reprinted from the Proceedings of the Entomological Society of 

 Londou, 18'J7, pp. xx.-xxxii., xxxiv.-xlvii.] 



PAPER, EXHIBITION, AND DISCUSSION ON 

 MIMICRY. (May 5fh, 1897.) 



Dr. DixEY read a paper on *' Mimetic Attraction." He 

 began by pointing out with the aid of diagrams that the 

 process of mimetic assimilation might start from a given 

 point and proceed along several divergent paths. For 

 example, from an ordinary non-mimetic form of neotropical 

 Pieris, such as Pieris phaloe, not one only but several diver- 

 gent series of mimetic modifications could be traced ; each 

 passing through a graduated series of closely-allied forms 

 until it terminated in a Pieris or Mylnthris bearing a more or 

 less intimate relation with some protected form or forms of 

 entirely different affinities. Such were the series leading 

 through P. cali/donia to P. demopMle $ , a mimic of Aeria 

 ayna ; the series starting from P. demophile and passing into 

 forms such as P. loemta ? , which was in mimetic relation- 

 ship with Heliconius atthis ; the series represented by P. pan- 

 dosia and P. leptalina, which approached Napeoyenes inachia ; 

 the series dealt with in a previous communication (Trans. 

 Ent. Soc. Lond., 1896, pp. G5-79), which led up to forms 

 associated with Heliconius numata ; and lastly, a series 

 derived from the one last-mentioned, which ended in 

 Mylothris aletJdna ? , a mimic of Tithorea tarracina. 



In all these instances, the model towards which the series 

 tended did not present an isolated scheme of colour, but was 

 a member of a larger or smaller group of forms, associated in 

 external features ; such as were shown in the series to be 

 exhibited by Mr. Blandford. These mimetic groups were no 

 doubt mainly of the " Miillerian " kind, that is, they were 

 associations between inedible species of various affinities. 

 Reasons were given for attributing great importance to the 

 operation of the Miillerian principle in producing such a 

 facies as that of the neotropical fauna, and for assigning to 

 Batesian mimicry a comparatively subordinate position. Stress 

 was laid on the facts (1) that Batesian mimicry could exist 

 only when the numbers of the mimic were insignificant 

 compared with those of the model, whilst a Miillerian group 

 was strengthened by every fresh accession ; and (2) that the 



