to limitations of the Milllcrian Hypothesis of Mimicry. 113 



teneas and lysander groups that I have examined. Finally, 

 there does not seem any reason to suppose that in these 

 Papilios the females represent a modification of the male 

 colouring. On the contrary, it appears far more probable 

 that the female pattern is the older, and that the metallic 

 patches of the males are a later development; indeed 

 there are several allied species in which they are non- 

 existent. 



IV. The suggested reciprocal resemblance between Pieris 

 locusta and Heliconius cydno galanthus. 



In Trans. Ent. Soc. 1896, p. 72 (note), Dr. Dixey sug- 

 gested tentatively that P. locusta, $ was a mimic of Helico- 

 nius mclpomene, so far as the under-side of the hind-wing 

 was concerned. In Trans. Ent. Soc. 1897, p. 325, this 

 idea was abandoned, and the very different H. cydno 

 galanthus was then definitely proposed as the model. The 

 resemblance however is certainly not of a kind to carry 

 general conviction. The most characteristic feature of the 

 under-side of the Heliconius consists of two curved chestnut 

 stripes right across the hind-wing, having their origin at 

 the middle of the inner margin. There is no trace of this 

 marking in P. locusta, nor, so far as I am aware, does it 

 occur independently in any American Pierines, although 

 its appearance is simulated in several mimetic species by 

 a prolongation of the lowest basal red spot. But the main 

 point at issue is the contention that "there is more reason 

 to suppose that the Heliconius has adopted certain features 

 from the Pieris (for example, the whiteness of the ground- 

 colour, and the disposition, if not the existence, of the 

 basal red marks) than that the converse alone has taken 

 place" (/. c. p. 327). The reasons in support of this belief 

 are not mentioned, but we have seen above that the con- 

 tention that the red basal spots have been produced, or 

 even materially affected, in Heliconius by Pierine influence 

 cannot be reasonably sustained. It remains only to deal 

 with the proposition that the white area on the under-side 

 of the fore-wing in the Heliconius must be explained by 

 its having directly mimicked the Pierine. Now the very 

 position of this white patch is of itself a serious difficulty 

 in the way of such an interpretation. The marking can 

 have no significance during flight, for on its upper-side 

 P. locusta $ has not the slightest resemblance to the 



TRANS. ENT. SOC. LOND. 1908. — PART I. (MAY) 8 



