1910.] FFtOM NORTHERN RHODESIA. 3 



The wet season in this valley, which has a comparatively small 

 rainfall, lasts from November to the end of March. This state of 

 things is accompanied by correspondingly marked seasonal phases 

 in the butterflies. In addition to those genera in which it is to 

 be expected, such as Precis, it is extremely noticeable among the 

 Acraeinse. In a very large number of species inhabiting this 

 valley, there is a marked tendency to a general dusky suffusion in 

 the individuals of the wet phase, especially among the females. 

 Dry season specimens, on the other hand, are very brilliantly 

 coloured. During the dry season the climate of the Luangwa 

 valley seems especially favourable to the Pierinse, which are 

 extremely dominant at that time. Indeed some species, such as 

 Pinacopteryx simana Hopff., which I did not meet with elsewhere, 

 were more abundant in thicket-covered country at that season 

 than at any other time. One of the peculiarities of the Luangwa 

 valley from a collector's point of view is the great scarcity of 

 tropical forest, more or less thin woodland being however plentiful. 

 Such forest as does occur is chiefly to be found in small patches 

 on stream-banks at the foot of the Mchinga escarpment on 

 the western side of the valley and in similarly broken ground 

 on the eastern side in Portuguese territory. In these forest 

 spots one finds species which are very rare or do not occur at 

 all elsewhere in the valley. Among them may be mentioned 

 Euphcedra neophron Hopff., Acrcea cabira apecida Oberth., Mela- 

 nitis libya Dist., and, at the height of the wet season, Liptena 

 homeyeri Dewitz. 



The butterflies generally of the Luangwa valley are much the 

 same as those of the tropical portions of S.E. Africa, though 

 some of the coast species which occur on the lower Zambezi and in 

 Nyasaland, such as Amauris ochlea Boisd., A. niavius dominicanus 

 Trim., Eronia buqueti Boisd., etc., appear to be absent, and such 

 species as Pseudacrcea ktcretia Oram, very rare. 



(2) The second region comprises the whole of the high plateau 

 country which forms the watershed between the Congo and the 

 Zambezi, and includes isolated patches of elevated land in the 

 Oongo basin. 



This country is characterised by its cool temperate climate and 

 relatively less marked seasonal change. The rains tend to begin 

 somewhat earlier and end later. One result of this is that the 

 abundance of butterflies and other insect life, associated with the 

 early spring in these regions, begins to be noticeable about the 

 middle of September, some six or seven weeks earlier than is the 

 case in the Luangwa valley. Indeed, it would appear that many 

 Lycamidse, more especially species of the genus Aphnceics, are on 

 the wing only about this time. 



There is a good deal of comparatively open country on this high 

 ground. With it are associated certain butterflies, among which 

 perhaps the more interesting are Belenois picta, here described for 

 the first time, the rare Papilio almansor Honrath, and, in Katanga, 

 the strangely coloured Zeritis zorhageni Dewitz. The remarkable 



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