The Bionomics of South African Insects. 421 



high bush at the edge of a wood, and thence giving chase 

 to other passing butterflies " (p. 237), 



In suggesting the seasonal relationships in the genus 

 Precis which he afterwards proved to exist, Mr. Marshall 

 speaks at the beginning of his first paper on the subject 

 (Trans. Ent. Soc. Lond., 1896, p. 557) of the special 

 interest which attaches to the alternations in this genus, 

 " not only on account of the great differences in the colour- 

 ing of their two forms, but also because of their marked 

 change in habits." 



He points out that the species of Precis in which there 

 is but little seasonal change {P. tvgcia, P. etgiva, and ]\ 

 natalicct) are, when at rest, leaf-like in both jjhases, although 

 they are more leaf- like in the dry season. He states that 

 they are furthermore especially forest insects, being 

 confined to " the warmer, low-lying, or heavily-timbered 

 districts." The other species of Precis in which the 

 seasonal forms are very different " occur more abund- 

 antly, or even exclusively, in the uplands and in open 

 country." There are, however, difierences of habit in 

 the species of the former group. Thus Mr. J. M. 

 Hutchinson is quoted by Mr. Marshall as stating that the 

 summer form of P. tugela " is a bolder insect, sailing 

 around and settling on trees at a fair height, almost after 

 the manner of Charaxes, whereas the other is much more 

 retiring, keeping among the thick bush and settling low 

 down, or on the ground among dead leaves, etc." {loc. cit., 

 p. 558). 



Turning to the second group of species iii which the 

 seasonal changes are pronounced, Mr. Marshall describes 

 the habits of P. simiia [cintilope'] (loc. cit., p. 560) : " Tiie 

 dry-season form only frequents the bush, settling on the 

 ground among the dead leaves, or very rarely on small 

 plants, the under-side colouring affording it excellent 

 protection. As the season advances the habits of the 

 insect cliange, and in October and November the later 

 form (c) may be found in company with the early form of 

 simia (b), frequenting open tops of kopjes, flying boldly 

 about within a limited area, and setthng with expanded 

 wings on shrubs and bushes. This is the habit of all 

 summer forms of Precis. . . ." With regard to P. scsamus 0, 

 Mr. Marshall remarks that it "differs from the normal 

 type of winter Precis in the absence of leaf-like colouring 

 below, and in the very slight falcation of fore-wings. This 



