Introduction. 
The vast continent of Africa, which extends in an unbroken mass over three zones, would scarcely 
lead one to suppose that it contains two utterly different faunas. As has been already explained in the 
Introduction, the Sahara, which is almost devoid of animal life, forms the division, and its almost complete 
lack of vegetation only permits a few species to cross over, which are practically independent of climate 
and specially powerful fliers. 
When defining the limit of the Palaearctic Region towards the south it has already been mentioned 
that the countries of the Atlas Mts. have no connection faunistically with the rest of Africa. Neither have 
they as regards climate. As far as the middle of the great desert a cold season prevails in North Africa 
at the same time as the European winter, though of very varying duration. In the Aures Mountains of 
Algeria this winter season lasts 6—8 months in the higher altitudes. Continuous, or often repeated, snowing 
up of the mountain passes is not uncommon in the higher parts of the Atlas Mountains, and long after 
every trace of snow has disappeared in Mid-Europe the peaks of the Moroccan Atlas and the cedar-covered 
Aures Mountains are crowned with dazzling white. 
But south of the Sahara there is no winter. Although in South Africa the temperature sometimes 
falls considerably at night and it is difficult to protect oneself from the severe cold, that does not prevent 
the sun from scorching down powerfully 12 hours later, and there is no hibernation of the vegetable world; 
it is changed into aestivation, for the vegetation dries up in the hot season and only puts forth tlowers 
and young shoots after the regenerating autumn rains. 
In true tropical Africa there is no break at all in plant-life and an always green and always leaf- 
covered vegetation grows here so thickly that in places the impenetrability of the Indian or Brazilian 
primitive forests is attained. But the region which is covered with these forests is not very large and is 
mostly broken up by grass-land. On the whole the steppe character predominates in Africa. 
The small number of high mountain ranges does not appear to favour the development of a very 
variable lepidopterous fauna. Only very few African districts will bear any comparison with the constantly 
varying character of Asiatic mountains, as the Himalayas, the Sunda Mountains or the Japanese mountain 
ranges, or again with the immense Andes range of America. Onty Abyssinia, Mount Kilima-Njaro and 
Madagascar show higher elevations and more deeply cut valleys, to which may be added the much more 
southerly Drakensberg. The mountains of the Cameroons, of Togo and Benguela, and the Nile mountains 
are not high enough to contrast faunistically with the surrounding lowlands, and the hills along the coast, 
the transverse chains which intersect the steppes and wastes of the vast interior, are scarcely more than 
dunes in character. 
The physical character of Africa is briefly as follows: The interior is a tableland, which quickly, 
often in terraces, slopes down to the sandy coast. Short but violent rainy seasons deposit upon this high 
land large masses of water, which run down to the sea in small but deep rivers. These dash over the 
terraces which lead down from the tableland to the coast, in wild cataracts, until the lowland at the coast 
is reached, where the masses of water fill the often enormous river-beds, overflow them and finally reach 
the sea in a many-branched delta. The floods occur, as a natural consequence of the highland rainy seasons, 
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