30 



fine variety from Entebbe presented by Mr. H. Eltringham it 

 will be seen that the bar is fused with the principal fulvous 

 marking. Papilio dardanus has not as yet been bred either at 

 Nairobi or in Uganda/ and this final proof that planemoides 

 belongs to the dardanus association is still wanting. Nevertheless, 

 a single specimen now before you constitutes in itself conclusive 

 evidence that planemoides has been rightly placed. This specimen 

 was collected by Captain T. T. Behrens in Buddu (1902-3), 

 and it is gynandromorphic on the left side, the yellow scales and 

 part of the dark markings of the male dardanus being dovetailed 

 into the pattern of the female planemoides.^ It is quite certain 

 that such an intermixture of characteristics can only occur 

 between the male and female of the same species, and that there- 

 fore planemoides is one of the female forms of dardanus. 



It is interesting to consider the probable causes of the relative 

 rarity of the mimetic female forms in Uganda ; hippocoon mimics 

 Amauris niavius, the most conspicuous Danaine, and probably 

 the most conspicuous butterfly of the African forests ; planemoides 

 mimics the highly conspicuous pattern of the male Planema 

 macarista and both male and female PI. poggei ; trophonius 

 mimics the ubiquitous Danaida chrysippus, but this is an open 

 country and woodland butterfly, not a forest species like its 

 mimic, and the two would only be commonly associated along 

 the borders of their respective stations. This relationship almost 

 certainly accounts for the fact that, although trophonius occurs 

 in all the subspecies of dardanus with mimetic females, it is 

 nevertheless invariably a rare form. Cenea mimics Amauris 

 echeria, which is excessively abundant in Uganda, the rarer 



1 Since this address was delivered, Dr. G. D. H. CARPENTERhassucceeded 

 in obtaining 26 eggs from a planemoides female on Bugalla, one of the 

 Sesse Islands, in the north-west of the Victoria Nyanza. He kindly wrote 

 to me early in the course of the breeding experiment, and, as I happened 

 to be publishing an article on P. dardanus at that time [Bedrock, April 

 1913. P- 42), I alluded to his investigations in the following words : " We 

 may anticipate that the offspring will be chiefly or entirely planemoides 

 and hippocoon." On the very day when I was correcting the proofs 

 (March 7th, 191 3), I received another letter telling me the results, namely 

 3 planemoides, 7 hippocoon and 12 males (I.e., p. 47 n.). The whole 

 family is now in the Hope Department. See Proc. Ent. Soc, Land., 1913, 

 pp. xxxiii-xxxv, also for June 4th. 



2 Trans. Eni. Soc, Loud., 1906, p. 297, PI. XVHI, Fig. 4. 



