578 Dr. F. A. T>ixo^rr2)hj to Mr. G. A. K. Marshall 



this precludes the female Pripilio from having been 

 retained by the help of Pierine influence within the limits 

 of the strong combination thus formed. Mr. Marshall's 

 opinion that the female pattern is the older is very likely 

 to be correct; it has always seemed to me the more 

 probable supposition ; though, in view of what may be 

 seen in many other groups, I should not venture to exclude 

 altogether the possibility that the female may have 

 dropped some characters once common to both sexes and 

 even gained others under the influence of mimicry or some 

 other form of adaptation. This is why I suggested in 

 1894 that the female Papi/ios had joined the Euterpe 

 combination whether by "discarding" or [supposing the 

 females to represent the older form] by "not adopting" 

 the brilliant colours of the other sex (Trans. Ent. Soc. 

 Lond., 1894, p. 298). It was pointed out by me many 

 years ago (Trans. Ent. Soc. Lond., 1890, p. lOG, note, 

 d fn/pos of Arf/jpmis diana $ ; and again in Proc. Ent. Soc. 

 Lond., 1894, p. xii, d p)ro2Ms oi A. nipihe %) that a mimetic 

 resen>blance may be attained by the help of the retention 

 of an ancestral character no less than by the development 

 of a new one. Mr. Marshall's point would only tell against 

 my suggestion if this possibility were ignored. 



The suggested reciprocal resemblance between Pieris locusta 

 and Heliconius cydno galanthus. 



Mr. Marshall begins his discussion of this case as fol- 

 lows:—" Li Trans. Ent. Soc, 1896, p. 72 (note), Dr. Dixey 

 suggested tentatively that P. locusta $ was a mimic of 

 Heliconius melpomcnc, so far as the underside of the hind- 

 wing was concerned. In Trans. Ent. Soc, 1897, p. 825, this 

 idea was abandoned, and the very different H. cydno galan- 

 thus was then definitely proposed as the model " (p. 113). 

 I shall hope for Mr. Marshall's forbearance if I venture to 

 point out that this is scarcely an accurate way of putting 

 it. My words in 189G were, "The underside of the hind- 

 wing in P. locusta, P. cinerea [I should now write Lepto- 

 Ijhohia cinerea'] and some others resembles that of Heliconius 

 melpomene and other protected species in giving the general 

 idea of a dark wing-area with yellow costal or precostal 

 streak and basal red spots." I have never "abandoned 

 this idea," which indeed is merely the expression of a 

 simple matter of fact ; but in 1897 I gave the general 



