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GAME FISH IN TANALAND 
tected by the Administration. In all the country on either 
side of the valley, i.e. Nyasaland and Mozambique to the 
sea on the east and the lake areas on the west, it does not 
exist. I am convinced that the former distribution of African 
water has had much to do with the distribution of its present 
fauna and native races. 
Giraffe, Oryx, one Gazelle, the Springbuck, White Bhino, 
and Ostrich are South African forms (south of Zambesi). 
They are also North African forms. There are many other 
instances. In the intervening belt, with its east to west 
distribution, they are unknown in the Central Lake areas. 
They probably reached South Africa by way of the Loangwa 
Valley on the east and Damaraland and Angola on the west. 
This theory I base on the present lines of zoological distribution. 
Conclusive evidence can only be obtained from the geology 
and palaeontology of these regions (Loangwa and Bangweolo), 
about which, in these respects, very little is known. 
The report of the Irrigation Commission on the Orange 
Biver basin, carried out some twelve or fifteen years ago by 
engineers from India, also contains some interesting facts 
regarding desiccation. 
GAME FISH IN TANALAND 
By B. Skene 
Koli-Koli 
Scombridce — near Tuna Group 
Migratory Habits . — During the first days of June the first 
koli-koli are caught — that is, as soon as the big rains are over 
and the sea inshore has become clear. They continue to 
increase in numbers till the end of September, when they 
reach their maximum. In October they begin to decrease, 
and go on decreasing till about the end of January. In 
February and March there are very few indeed. In April and 
