POPULAR SCIENCE 



SOME AFRICAN BUTTERFLIES 



By HERBERT MACE 



Little by little the secrets of the once " Dark Continent " are 

 being given up, as European civilisation presses slowly down 

 from the North or up from the South. Comparatively speaking, 

 however, but little is yet known, for both nature and the human 

 inhabitants seem determined to hold back their secrets till the 

 last moment. 



From the biological point of view, the Continent seems 

 remarkably uniform, and has been consolidated for purposes of 

 classification into one region — the Ethiopian. Not quite all 

 of Africa comes under this denomination, however, for the 

 barrier between this and the Palaearctic region is not, as one 

 might at first sight suppose, the Mediterranean. Comparatively 

 narrow even in its widest part and extremely so in its narrowest, 

 it would scarcely prevent the frequent intermingUng of forms 

 from both its shores at the present time. Moreover, geo- 

 logically speaking, it is quite recent and the real barrier between 

 the two regions is the Great Desert, the one-time ocean, which 

 lies to the south of the Mediterranean Httoral countries and 

 is passed only with difficulty by man, while the humbler forms 

 of life find it a more effectual barrier than mountains or seas. 



The northern coast, including Lower Egypt, has a butterfly 

 fauna not greatly different from that of the Southern European 

 countries, and it is only in Upper Egypt and the Sudan, where 

 the Nile Valley forms a slender link between the two regions, 

 that we come across characteristically Ethiopian forms. 



South of this point there is, considering the enormous 

 number of butterfly species which have already been found on 

 the continent, wonderful uniformity of species, and very few 

 forms indeed are identical with those familiar to the European 

 butterfly collector. In such a vast area there are naturally 

 species present in one country which are absent from another ; 

 but, just as the now extinct Large Copper, once confined to the 



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