24 EINAR LÖNNBERG, MAMMALS COLLECTED BY THE SWEDISH ZOOLOGICAL EXPEDITION ETC. 
and the others abolished, but the facts mentioned form another of the numerous 
proofs that many members of the typical fauna of a subregion extend into other 
subregions as well, if suitable conditions of life in accessible districts are 
offered to them. On this depends the distribution. 
Since »the Geography of Mammals»> appeared also several important discoveries 
of new mammals characteristic of the West African forest region have been made.' 
The one which created most interest was probably the Okapi, but it is also striking 
that the first specimen of a new genus Hylochoerus which evidently is a typical 
forest mammal was obtained at Mau, British East Africa, outside of the West African 
forest region, although later on it was proved that members of this genus live in 
the Kongo forest, in Cameroon and so on. 
Before an investigation is made whether any West African mammals have been 
obtained by this expedition in British East Africa the discussion about the two 
other subregions of SCcLATER's system ought to be continued. The »Cape Subregion» 
as defined above includes WALLACE's South African and the southern half of his 
East African subregion. 1t was undoubtedly a step in the right direction to unite 
these two subregions as they have proved to be more similar with regard to their 
faunas than was known when WALLACE wrote his book on geographical distribution, 
but it is more uncertain whether the limitation towards the north of SCLATER's 
»Cape subregion> is successfully chosen. 'The name is certainly not very characteris- 
tic. It is true that »Cape»> or South Africa has a certain number of endemic mam- 
malian genera as for instance Cymictis, Suricata, Petromys, Bathyergus, Pelea etc. 
and probably is Chrysochloris still more typical for South Africa, although some of 
its species reach much further north. There are also some endemic species like 
Hycena brunnea, Equus zebra a. o. but they have near relatives further north. Very 
little of the fauna belonging to SCLATER's »Cape Subregion» can be supposed to 
have its origin in South Africa, or even to be especially characteristic for that 
country. Not a few of the genera enumerated by SCLATER as typical for this »sub- 
region» extend according to what we know now beyond its proposed northern boun- 
daryline for instance Apyceros, Pachyuromys, Myoscalops, Proteles, Otocyon, Rhyncho- 
cyon and Myosorex. 
The »Saharan Subregion» according to ScLATER's definition appears to be arti- 
ficial. Its easternmost portion, Somaliland with its beorderlands form a zoogeogra- 
phical centre of its own with several endemic mammals, for instance not less than 
three genera of antelopes, Ammodorcas, Lithocranius and Dorcatragus to which might 
be added Strepsiceros imberbis, further the rodents Heterocephalus, Fornarina and Pec- 
tinator. In Somaliland is the centre for the genus Rhynchotragus as well. There live 
also the aberrant Grévy's Zebra and the Somali Ass in addition to several other 
endemic species of genera with a wider distribution. But these characteristic mem- 
bers of the Somali fauna do not extend their distribution westwards through Sudan 
' But at that time 1899, there were already several typical West African mammals known which are 
not mentioned, as f. i. Idiuwus, Zenkerella, Limacomys ete., and in addition to these genera a very great num- 
ber of species. 
