the charina Group of Pinacopteryx. 205 



called sickle-shaped. The scent-scales in two males from 

 the Voi River (fig. 9) and one from Mlegwa are of the 

 liliana rather than of the simana type. The basal expan- 

 sion takes up more of the lamina and is more rounded 

 than in simana, but is much smaller and less rounded 

 than in liliana. Like the corresponding structure in 

 the latter form, the lamina shows a dark, granular, 

 circular or oval patch at the junction of neck with body 



(%• 9, P)- 



(5) P. venata, Butl. — This is the form which is found 

 in the White Nile region, Abyssinia (Lake Rudolph Expe- 

 dition), Southern Kordofan and the Southern Sudan at 

 least as far west as the Shari-Tchad Protectorate. It is 

 generally smaller than P. simana, and, especially in the 

 dry season, is sharper- winged in both sexes than that 

 insect. The upper surface of the male differs also from 

 that of P. simana in showing no dark veining; it may 

 possess in the wet season a few black scales in the situation 

 of the discocellular spot of the fore-wing, but is generally 

 destitute of all traces of these spots except a slight dis- 

 coloration showing through from beneath. The fore-wing 

 possesses a dark apical patch passing into a hind-marginal 

 band; this patch and band in the dry season may become 

 pale and may almost disappear. There is also on the 

 hind-wing a row of marginal spots, often absent in the 

 dry season. Beneath, the male is white ; in the wet season 

 the submarginal series is very often absent, but may be 

 indicated by a more or less complete chain of dark spots. 

 In the dry season the submarginal chain is usually better 

 developed; it is paler in colour, and on the hind-wing 

 frequently forms a festooned linear band. A slightly- 

 marked brownish irroration may be present on the hind- 

 wing and the apex of the fore-wing. There is generally 

 some dark veining on the apex of the fore-wing and outer 

 portion of the hind- wing at both wet and dry seasons. 

 The discocellular spots are always present; a marginal 

 row may also occur, especially in the wet season. On the 

 upper surface of the female the dark apical patch is broader 

 than in the male ; as in that sex, it passes into a con- 

 tinuous hind-marginal band, darker and more pronounced 

 in the wet season than in the dry. In the wet season the 

 dark veining of both wings is usually well marked, as in 

 Mr. Butler's type ; the hind-wing also carries a series of 

 large dark marginal spots. The submarginal chain of the 



