South- African Butterflies. 75 



sexes described above^ Mr. Bowker having repeatedly 

 observed them in copidn, and having forwarded to me 

 two pairs captured by him in that condition. A well- 

 established case of this description affords us something 

 like reliable grounds for reconciling other so-called "dis- 

 tinct species/^ and resolving them into the differing sexes 

 of one insect. Every year's discoveries prove to us that 

 arbitrary entomological decrees of divorce are far more 

 numerous in our collections than we had any idea of. 

 The determination, bej^ond dispute, of the 9 Echerioides 

 has led me to search for the same sex of P. Cynorta, 

 there being only c?s of the latter in the National and 

 other collections. I have found, it is true, nothing re- 

 sembling the 9 Echerioides ; but, placed next to P. Cy- 

 norta, in most arrangements, is the P. JBoisduvalUanus of 

 Westwood, an insect only differing from Cynorta in the 

 arrangement of the white markings of the anterior wings, 

 — the very character by which the $ Echerioides seems, 

 at first sight, so remote from the ^ . BoisduvaUianus 

 most accurately imitates the colouring and pattern of 

 AcrcBa Gea, Fab. ($), another West- African butterfly; 

 — how closely may be inferred from the fact that asso- 

 ciated with three specimens of the Papilio in the British 

 Museum I found an example of the Acrma ! — but the 

 resemblance is scarcely more remarkable than that exis- 

 ting betAveen the $ of P. Echerioides and Banais Echeria. 

 Both the perfect examples of Papilio BoisduvaUianus 

 in the National Collection are 9 s ; the third wants the 

 abdomen, but all its characters coincide with those of the 

 two others ; and the only example in Mr. Swanzy's collec- 

 tion (from the Gold Coast) is of the same sex. All the four 

 specimens of P. Cynorta: in the British Museum, as well 

 as others in the Hope Museum, and in the collections of 

 Mr. Salvin and Mr. Hewitson, are ^s. I am convinced 

 after careful comparison, and from analogy with the case 

 of Echerioides, that P. BoisduvaUianus is the $ of Cy- 

 norta ; and should this be eventually proved, a better 

 distinction between the two species, the c? s of which are 

 so nearly alike as those of Cynorta and Echerioides, could 

 not be wished for, than the fact of one ? wearing the 

 livery of an Acrcea and the other that of a Dartais.* 



* The poiut in which the ? Echerioides most differs from Banais Eche- 

 ria, and most resembles as well as its own S as P. Cijnorta and P. Bois- 

 duvaUianus, is in the basal colouring of the underside of the hind-wings, 

 which is almost identical in all the four. 



