TRANSACTIONS OF SECTION D. 429 
M. Delhez has not resulted in a single addition to the list of Species. The Gambia, 
on the other hand, is now much better known than it was, thanks to the two 
visits of the late Mr. Budgett, to whom we owe the discovery of two species. But 
it is the Niger which, through the collections made by Dr. C. Christy, the late 
Captain G. F. Abadie, Mr. Budgett, and especially Dr. Ansorge, has been pro-~ 
ductive of the most important additions to our knowledge. The most striking 
discoveries are the type of a new family, Phractolemus, since rediscovered in the 
Ubanghi, and Polycentropsis, the first representative of the Nandide in Africa. 
Leaving aside species entering the sea, we now know fifty-four species from the 
Senegal, forty-one from the Gambia, and ninety-six from the Niger, the lower 
course of the latter being the most productive. A remarkable feature of these 
rivers is the comparative paucity of Cyprinids, and the total absence in the first 
two of the genus Barbus, which also appears to be absent from the Chad 
basin. 
Our knowledge of the piscine inhabitants of the rivers flowing into the 
Atlantic between the mouths of the Gambia and of the Niger has also made con- 
siderable progress. The fishes of Liberia, collected by Dr. Biittikofer, have been 
described by Dr. Steindachner, and those of the Gold Coast, collected by the late 
Mr. R. B. Walker, have been reported upon by Dr. Giinther. Sixty-seven species 
are on record from this district, twenty-four of them being endemic. 
Further South, North Cameroon has yielded several additions, for a know- 
ledge of which we are indebted to Dr. Lénnberg, whilst South Cameroon, together 
with the Gaboon district, has been diligently explored by Mr. G. L. Bates, with 
the result that a great number of new species have been brought to light. This 
part of Africa is specially interesting from the fact that its rivers interlock with 
the head waters of the Sanga, which belongs to the Congo basin, and, the fishes 
being mostly the same in both watersheds, in that district, a sort of passage is 
established between the Gaboon and Congo faunas. Among the most remarkable 
forms discovered by Mr. Bates we may mention the genera Microsynodontis, 
Allabenchelys, and Procatopus. Since Dr. Sauvage reported, twenty-five years 
ago, on the fishes of the Ogowe, a small collection has been made by the late 
Miss Kingsley, and described by Dr. Giinther, and a number of new species have 
been characterised by Dr. Pellegrin. The number of species now known from 
this part of Africa amounts to eighty-seven for South Cameroon and the Gaboon, 
and fifty-four for the Ogowe. Very curiously, among them we miss Polypterus 
and Calamichthys, which occur in the Lower Niger and Old Calabar, and again 
in the Chiloango—a remarkable instance of discontinuous distribution, which 
Se be accounted for by physical conditions, so far as we are acquainted with 
them. 
The Congo system (exclusive of Lake Tanganyika), from which only about 
ninety species of fishes were known ten years ago, proves to be far richer than 
any other, for, incompletely explored as it still is, it has already furnished examples 
of 265 species, forty-five of which have been added since the publication of the 
work ‘Les Poissons du Bassin du Congo’ in 1901. In fact, every collection made 
even in its most accessible parts adds new species to the list, and many of its 
rivers have never yet been fished for scientific purposes. No doubt we do not 
know more than two-thirds of the fishes of the Congo. The riches in Mormyrids, 
Characinids, Silurids, Cichlids, Mastacembelids, is something surprising, not only 
in the number of species, but also in their extraordinary variety of structure ; 
and as many as seven species of Polypterids, out of the eleven that are now 
known, occur in this river-system. With the exception of the Cromeriide and 
lel all the families known from the sub-region have representatives in the 
‘Congo. 
Lake Tanganyika, now forming part of the same hydrographic system, has 
a somewhat different fauna, consisting mainly of Cichlids, to which we have 
‘specially alluded in an earlier part of this Address. But there are, in addition, 
a number of Silurids and Cyprinids, a few Mastacembelids and Characinids, a 
Cyprinodont, and a Polypterus. The latter belongs to a species otherwise restricted 
to the Congo, and of the four Characinids two are Congo and two are Nile forms. 
