riEKIX.'E. 187 



cellular spot rather larger than in ^, with a silvery-white centre, and 

 almost invariably accompanied by a similar spot immediately sur- 

 mounting it, and by a third (commonly larger) one immediately pre- 

 ceding it, and so within discoidal cell ; at base, immediately below 

 origin of subcostal nervure, a ierruginous-red mark ; eight spots of 

 irregular discal row varying from dull-reddish to ferruginous, some or 

 all of them often indistinct or almost obsolete. In both wings the 

 minute spots of the hind-marginal nervular series are dark and dis- 

 tinct and bordered inwardly by some pink scaling. 



As indicated in the foregoing descriptions, there is some diversity 

 in the markings of the $, chieily as relates to the development of those 

 of the under side ; but the two forms of the $ present a far greater 

 discrepancy, one scarcely differing from the $, while the other is 

 sulphur-yellow above with conspicuous disco-cellular and hind-mar- 

 ginal spots, and deep ochreous-yellow beneath, with one or two addi- 

 tional disco-cellular spots. There exist, however, several linking 

 variations between these two forms of ^, but almost all that I have 

 seen "^ are nearer to the yellow than to the white form. These $ s are 

 either simply of a paler yellow, or exhibit a more or less extensive 

 suffusion of white over the discal area of one or both wings. The 

 Hyhlcea of Boisduval, from Senegal, is one of the former category, and 

 the Alcurona of Butler, from Abyssinia, one of the latter ; and it is 

 noteworthy that in both cases the describers mention only one terminal 

 disco-cellular spot on tlie under side of hind-wing, — a feature charac- 

 teristic of the white $ and of the $. A fine example of the full 

 yellow coloration, taken near D'Urban by Colonel Bowker, also pre- 

 sents this solitary spot. 



In South Africa, the yellow or Rhadia form of $ appears to pre- 

 dominate ; out of 47 examples from all quarters, I find 26 yellow, 7 

 intermediate, and 1 4 white. These different ^ s are not local forms, 

 but occur together (as Mr. Butler, Proc. Zool. Soc. Loud., 1884, p. 

 486, has shown to be the case at Aden) in several places. For 

 instance, I have white, yellow, and intermediate $ s from the Bashee 

 Eiver and Potchefstroom in the Transvaal ; and Mrs. Barber informs 

 me that all three flew in the neighbourhood of Kimberley in the 

 autumn of 188 1." I have met with both white and yellow % s among 

 the stragglers that occasionally find their way to Cape Town, and have 

 received the two forms together from Springbokfontein in Namaqua- 

 land. As respects Tropical Africa, I have noted the two in collections 



^ The exceptions are two very slightly yellowish-tinged 9 s from Aden, and a dwarf 

 (exp. 2 in. I lin.) ? , taken by Colonel Bowker in some South-African locality not specially 

 noted, which is somewhat more yellow-tinged along hind-margins, and has in the fore-wings 

 the disco-cellular spot very small and faint, and the reddish Iiind-margiiial spots minute and 

 indistinct. 



- Mrs. Barber adds (12th September 1883) : " I have seen both white and yellow ? s lay- 

 ing their eggs on the same plant, and have reared the caterpillars, which produced butter- 

 flies of all the different tints that exist in this species." 



