206 Dr. F. A. Dixey on 



fore-wing ends in a large spot between the second and 

 third median branches ; there is no spot below the median, 

 such as occurs in P. liliana. A discocellular spot is present 

 on both wings in the wet season; in the dry season it is 

 often absent from the hind-wing, and sometimes from 

 both. Beneath, the hind-wing and apex of the fore-wing 

 are yellow, varying in degree of intensity ; the remaining 

 area of the fore-wing is white, often with a yellowish shade 

 at the base. The veins of the hind-wing and of the apex 

 of the fore-wing are marked with dark lines, paler in the 

 dry season ; at which period the same areas may also 

 show a slight reddish-brown irro ration. Except in the 

 extreme dry-season form, a marginal row of spots is 

 generally to be found on the hind-wing. The submarginal 

 series of spots is usually present at both seasons, on the 

 hind-wing taking the form of a more or less continuous 

 festooned line; on the fore-wing it may be very slightly 

 developed, but always includes the characteristic spot 

 between the second and third median. As on the upper 

 surface, there is no spot posterior to the median. Dis- 

 cocellular spots appear to be always present on both 

 wings. It may be observed that the dry-season specimens 

 from the White Nile are sharper-winged than the generality 

 of examples from Kordofan, and are also more conspicuously 

 marked. It is especially noticeable in the latter assemblage 

 that all the markings of the female on both surfaces are 

 in the dry season of the same reddish-sandy tint. In the 

 wet season the corresponding markings are dark brown or 

 black. The clasper of a male from Gondokoro ends 

 posteriorly in a spine (tig. 5) which is much blunter than 

 that of P. charina, liliana or gerda, but is slightly less 

 blunt than that of a P. simana from ( iazaland. The uncus 

 (fig. 15) is like that of P. simana, but is still more sharply 

 licnf downwards at the tip. The scent-scale (fig. 12) is 

 somewhat variable; but on the average is shorter, and 

 broader in proportion than that of P. simana, which it 

 otherwise resembles. 



P. simana and P. venala are no doubt closely related, 

 though typical specimens are easily distinguished. They 

 may perhaps intergrade in Uganda. 



The chief points of distinction between Pinacopteryx of 

 the charina group may be summarised in tabular form as 

 follows : — 



