28 MR. GtiT A. K. MABS&AtL ON THE [Jan. 19, 



doubtless seem to many at first sight to be unwarranted, but after 

 a careful study of a large number of insects, including many type- 

 specimens, I can arrive at no other conclusion. Speaking roughly, 

 the position is as follows : — On the eastern side of the Continent 

 we have T. omphale, with its heavy black bars in both wings, during 

 the wet season, which is replaced during the winter by its dry- 

 season form T. ilieogone, in which the black bars disappear more or 

 less completely ; the black borders are much reduced, and the 

 underside of secondaries becomes speckled with grey hatching, with 

 a darker transverse bar on disc. But, as so often happens in such 

 cases of seasonal dimorphism, at the change of seasons specimens 

 are met with uniting the characteristics of both wet- and dry-season 

 forms. Some such examples were caught by the late Mr. E. C. 

 Buxton in Xatal and Swaziland, ^hich resem.ble T. iheogone in 

 their shape and in the absence of the black bars, but have the 

 border of the apical patch as in T. omjihale, and the underside is 

 white, without trace of grey hatching. These were referred, and 

 I think justifiably, to T. evippe by Mr. Trimen (=^pseudocale, Butl.), 

 who at that time regarded T. omphale and theogone as distinct species. 

 In Eastern Africa, therefore, we have T. evlppe as an intermediate 

 seasonal form of T. theogone-omphale, and this is probably also the 

 case in Angola, on the West Coast ; but when we reach Guinea 

 and Sieri-a Leone T. evippe is the predominating form, and the 

 extremes are apparently very scarce, or even absent, this being 

 perhaps due to a greater uniformity of general conditions, which 

 might tend to produce a mean or intemnediate form. The question 

 then arises whether T. evippe is specifically distinct from T. omphale. 

 Personally I think not, but I regard it as a local development or 

 variation of that species, which still exhibits a series of gradations 

 linking it to the parent form. Then by the law of priority evippe 

 must stand as the name of the species, and T. omphale be ranked 

 as a local variety. 



T. omphale, as defined by Trimen (S. Afr. But.), ranges practically 

 throughout Africa, south of the Equator ; to the north of this it 

 is only recorded from Seuegambia (Hope Coll., Oxford) and 

 Abyssinia, and appears to be very scarce all along the West Coast. 



T. hyhridus is another example of intermediate seasonal colora- 

 tion, i*esembling the summer T. omphale above and the winter 

 T. iheogone below ; the type is'from Plettenberg Bay, Cape Colony. 



T. complexivus (Delagoa Bay and Somaliland), omphaloides 

 (Natal, Ztiluland, Swaziland, Transvaal, and Kilimanjaro), and 

 corda (Swaziland) are also intermediate, but nearer the dry-season 

 form than T. hyhridus, as they have the upperside black markings 

 more reduced, the black bar in hind wings being usually obso- 

 lescent and often absent. In the latter case they constitute the 

 AnthocJiaris theogone var. B of Boisduval. 



T.epigone,irom Zomba,theM'^hite Nile, and Arabia, is inseparable 

 from T. theogone. The single female in the British Museum from 

 Ai'abia is of interest, having lost all the discal black markings 

 (probably as a result of the arid climate), and thus represents an 

 extreme example of local dry-season coloration. 



