in Butterflies of the Genus Precis. 33 



blackish ; from the vertex spring two spines similar to those 

 on the body but half as long again, stouter and somewhat 

 clubbed instead of sharply pointed. Legs and prolegs 

 shining black, the latter with apical third part light yellow. 

 The dorsal yellow markings are variable in development 

 and occasionally absent. The pupa also presents two forms 

 of coloration : one, the gilded form, usually characteristic 

 of the dry season, has already been described by Mr. Trimen 

 (S. Afr. Butt. vol. iii. App. p. 401) with his wonted clearness 

 and thoroughness of detail; the other differs only in being 

 entirely dull brownish black, with two subquadrate shiny 

 black patches on wing- covers. 



The colouring of the larva, judging by the few examples 

 I have examined, is not affected by season, and the greater or 

 less development of the yellow markings does not seem to 

 bear any intimate relation to the two forms of imago. The 

 sharp and thickly-set branched spines are doubtless an 

 (fficient defence against certain enemies and perhaps account 

 for the general lack of procryptic colouring in the larvre of 

 this and allied genera. But despite their somewhat noticeable 

 appearance and the comparative commonness of the perfect 

 insect, my diligent search for larvaj has met with a singular 

 want of success. Up to the present I know of only two 

 enemies that attack the larva : one is a small ichneumon 

 which kills it before it is one-third grown ; the other is a 

 Hemipteron of the family Lygeeidaa, which has a predilection 

 for caterpillars of all kinds, even to hairy monsters 6 inches 

 long. Both forms of pupa are certainly procryptic in 

 colouring. During the moist summer months the withered 

 leaves of the food- plant turn dark brown or black, instead of 

 yellow as in the winter, so that in both cases the pupa is 

 well adapted to its surroundings, looking like a bit of shrivelled 

 leaf. In one instance I have bred the wet-season form from 

 a golden pupa, but I have not yet reared typical sesamus from 

 the dark form. 



The differences between the seasonal forms of the imago 

 are not confined to shape and colour alone, but there is like- 

 wise a very appreciable divergence in habits, which has been 

 referred to by Mr. Trimen. Speaking broadly, the natalensis 

 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 sesamus form is moie 

 partial to shady spots, and is to be found in ravines and 

 sprints or rocky wooded slopes, and shaies with the Hesperid 

 barangesa ntotczioides, Holl., a marked affection for disused 

 mining-shafts and cultings. This distinction must not be 



Ann. tfc Mag. N. Hist. Ser. 7. Vol. ii. 3 



