422 Mr. G. A. K. Marshall on 



is accoimted for by its different habits, for instead of 

 frequenting dead leaves in the bush it prefers the dark 

 rocks on stony and wooded kopjes." Evidence is brought 

 forward to show that P. artaxia only exists in the cryptic 

 dry phase in the warm timbered coast belt, although it 

 develops a much less well-concealed wet-season phase 

 {nachtigalii) in open country (pp. 561, 562). 



In his second paper on the subject (Ann. and Mag. Nat. 

 Hist., ser. 7, vol. ii, July 1808, p. 30) Mr. Marshall gives a 

 further account of these interesting differences in habits : 

 " Speaking broadly, the oiata/cnsis form frequents the 

 highest points in any neighbourhood, especially if they be 

 more or less open (for it is anything but a sylvan insect) ; 

 whereas the scsamus form is more partial to shady spots, 

 and is to be found in ravines and spruits or rocky wooded 

 slopes, and shares with the Hesperid Sarancjcsa diniinaia 

 a marked affection for disused mine-shafts and cuttings. 

 This distinction must not be taken too strictly, for true 

 sesamvs is occasionally found in company Avith the summer 

 form on open hill-tops, but principally at the change of 

 seasons ; but natalcnsis, so far as my experience goes, is 

 never to be found in the more shady stations frequented 

 by sesamns. The latter, moreover, is distinctly warier and 

 more difficult of approach when not feeding, and if alarmed 

 flies off with a rapid, and often zigzag, flight, settling 

 abruptly among rocks or herbage, when its greenish-black 

 under-side colouring is equally protective. Sesamus is 

 more often observed in gardens, and not unfrequently 

 enters human habitations in search of a shady resting- 

 place." Mr. Marshall also quotes Mr. J. M. Hutchinson's 

 experience on his farm in Natal, lying in an open plain 

 between two ranges of hills : " He has found sesamus 

 resident on the farm, occurring fairly connnonly along the 

 banks of the spruits during the winter, whereas natalensis 

 is very much scarcer and non-resident, the examples .seen 

 having always been travelling from one range of hills to 

 the other, on both of which it is common." 



Since his return to England, in the present summer, 

 Mr. Marshall has summarized his experience of the habits 

 and stations of the seasonal phases of the species under 

 discussion as follows : — 



" There are three types of .stations in South Africa which 

 may bo occupied by butterflies of this genus. 



I. Forest country, with heavy timber affording deep 



