52 



on the mainland in the neighbourhood of Entebbe. Corresponding 

 with the relative scarcity of the models, the island Pseudacrœas 

 are more variable and more connected by transitional forms 

 than on the mainland. The islands were in fact ideal spots on 

 which to test Dr. Karl Jordan's conclusion that Pseudacrcea 

 hobleyi, terra, and obscura, were the polymorphic forms of a 

 single species.^ Dr. Carpenter's numerous transitional forms 

 certainly afforded strong support to Dr. Jordan's inference, but 

 the speaker hoped for still more convincing and indeed incontro- 

 vertible evidence. For many weeks Dr. Carpenter had been 

 vainly trying to obtain ova from female Pseudacrœas in Bugalla 

 Island, but at length, on June i6th last, he observed an egg laid 

 by a female obscura with distinct traces of the pattern of hobleyi. 

 The parent escaped, but the egg hatched and the caterpillar 

 flourished, and Dr. Carpenter had written : 



" There is just time for the egg, larva and pupa to develop 

 before the Congress at Oxford is over, so that should the offspring 

 be terra or hobleyi I will let you know. As of course there w^ill be 

 no time to write, I will cable, just the one word, either hobleyi or 

 ierra. If it is obscura I won't cable, but will, of course, write. 

 I feel that it will be such a splendid opportunity for making this 

 result known, when you will be showing the Pseudacrseas with 

 especial intent to prove their conspecificity by the intermediate 

 forms." 



The cable had not yet arrived, but the speaker hoped that the 

 result might yet be announced to the Congress at a future meeting.' 

 Although he had not been able as yet to publish this result. 

 Prof. PouLTON felt sure that members of the Congress would 

 appreciate the splendid work done by these two naturalists in 

 Uganda, and the fact that each of them had thrown so much light 

 on the results achieved by the other. 



1 " The Systematics of some Lepidoptera which resemble each other, 

 and their bearing on general questions of Evolution," by Dr. Karl Jordan, 

 /. Congr. Int. Eni., Bmx., 1910, pp. 385-404. 



2 The cable with the word " terra " reached Prof. Poulton in the Isle 

 of Wight, on August 19th, 1912, nine days after the end of the Congress. 

 The discovery was published in Nature for Sept2mber 12th, 1912, p. 36, 

 and on November 6th the specimen itself was exhibited, together with other 

 Pseudacra>as bred on Bugalla by Dr. Carpenter, at a meeting of the 

 Entomological Society of London {Proceedings, 1912, pp. cxiv-cxviii.). 



