PHASES OF NATURE AROUND PRETORIA. 41 



and with great effect on the questions of " mimicry " 

 and " protective resemblance." It has been eloquently 

 remarked by Mr. Bates, that on their wings " nature 

 writes as on a tablet the story of the modifications of 

 species, so truly do all changes of the organization register 

 themselves thereon " *, and a cabinet of butterflies in 

 the possession of a competent naturalist now not only 

 exhibits what used simply to be called the " works of 

 nature," but absolutely in many cases shows how nature 

 works. Hamanumida dcedalus, formerly and generally 

 quoted by its better-known synonym Aterica meleagris, 

 has been recorded as a good instance of " protective 

 resemblance." Mr. Wallace has recently stated that 

 it "always settles on the ground with closed wings, 

 which so resemble the soil of the district that it can 

 with difficulty be seen, and the colour varies with the 

 soil in different localities. Thus, specimens from Sene- 

 gambia were dull brown, the soil being reddish sand 

 and iron-clay ; those from Calabar and Cameroons were 

 light brown with numerous small white spots, the soil 

 of those countries being light brown clay with small 

 quartz pebbles; whilst in other localities where the 

 colours of the soil were more varied, the colours of the 

 butterfly varied also. Here we have variation in a 

 single species, which has become specialized in certain 

 areas to harmonize with the colour of the soil f. But in 

 the Transvaal this butterfly never settles on the ground 

 with closed wings, and the only example sent from 

 Durban by Colonel Bowker to Mr. Trimen was described 

 as " settled on a footpath with wings expanded " $. I 

 saw and captured a large number of specimens, and 

 always found them resting with wings expanded, and 

 nearly always on greyish-coloured rocks or slaty-hued 

 paths, with which the colour of the upper surface of 

 their wings wonderfully assimilated. Large tracts of 

 bare ground of a reddish-brown colour exist with which 

 the under surface of the wings would be in perfect 



* * The Naturalist on the Amazons.' 



t 'Darwinism,' p. 207. 



t ' South African Butterflies,' vol. i. p. 310. 



