TRANSACTIONS OF SECTION D. 425 
endeavoured to show that a Tertiary land conneetion between Africa and South 
America is not absolutely necessary to explain the many points of agreement 
between the fresh-water fishes of these two parts of the world, as has been 
postulated by many writers. Besides, there are still some who hold, as does 
Professor G. Pfeffer—whose interesting essay on the zoo-geographical conditions of 
South America, from the point of view of lower vertebrates, appeared after this 
Address had been written—that a former subuniversality of distribution will afford 
a solution to many of these problems without necessitating such a land-con- 
nection, as exemplified by the past distribution of the Pleurodiran Chelonians, 
In this review we have summarised many previous hypotheses and added a few, 
but in every case with a feeling of dissatisfaction, fully realising, as we do, the 
futility of speculations in the present state of the two great branches of know- 
ledge, geology and paleontology, on which the solution of these questions must 
ultimately rest. 
We may now pass on to the realm of facts, and survey in the briefest manner 
the waters of the great continent as they appear after the many discoveries which 
have of late so greatly increased our knowledge of the African fishes. Much, 
very much, remains to be done before we can claim an approximately sufficient 
acquaintance with the faunas of the different districts, so many of which are still 
unexplored as far as fishes are concerned. But we have reason to rejoice at the 
rate at which our knowledge has progressed within the last few years, and I 
may here pay a tribute of gratitude to the many explorers who, among hardships 
and dangers of all kinds, have found it possible to devote some of their energy 
to the collecting of fishes, a group of animals which offers special difficulties of 
preservation and transport. Among those who have done most in this line within 
the last ten years I must mention the names of Mr. Moore of Tanganyika fame 
and his successor in the same field, Mr. Cunnington; Mr. Loat, whose three 
years’ fishing in the Nile has resulted in a splendid collection, now being 
worked out under the auspices of the Egyptian Government in response to an 
appeal from the late Dr. John Anderson; Captain Wilverth, Major Cabra, Captain 
Lemaire, Captain Hecq, and other Belgian officers in the service of the Congo 
State; Mr. G. L. Bates, who is still adding to our knowledge of the South 
Cameroon and Gaboon districts; the late Miss Kingsley, who collected in the 
Ogowe; Captain Gosling, who has sent home a fine series of the fishes of Lake 
Chad; Dr. Ansorge, who, after making important discoveries in the Niger Delta, 
has passed on to the exploration of Angola; Mr. Degen, in Abyssinia; Dr, 
Donaldson Smith, Mr. Hinde, Mr. B, Percival, Mr. Oscar Neumann, and the late 
Baron Carlos von Erlanger, in East Africa; and, lastly, three who have sacrificed 
their lives in the service of zoology: Paul Delhez (Congo, Senegal), Doggett 
(Lake Victoria), and J. S. Budgett, to whose loss I have already alluded. 
Here in South Africa, through the generosity of Mr. C. D. Ttudd, a systematic 
zoological survey, which promises to yield important results, is now being carried 
out by Mr. C. H. B. Grant, formerly of the British Museum, who has proved him- 
self to be a most painstaking and successful collector. 
In the present state of our knowledge of the fresh-water fishes Africa may be 
divided into five sub-regions, the discussion of the further subdivision of which 
would exceed the limits of this Address :— 
1. The North-Western Sub-region, or Barbary, and the Northern Sahara, 
properly forming part of the Palearctic region. 
2, The Western-Central Sub-region, with all the great rivers and lakes, 
extending to the Nile Delta and the mouth of the Zambesi, for which the term 
Megapotamian Sub-region has been suggested to me by Dr. Sclater. 
3. The Eastern Sub-region—A byssinia, with the upper tributaries of the Blue 
Nile, and the countries east of the Rift Valley and north of the Zambesi. 
4, The Southern Sub-region—all the waters south of the Zambesi system. 
5. Madagascar. 
The smaller islands of the Indian Ocean have a fresh-water fish-fauna so 
insignificant that they may be entirely neglected in a broad divisjon of the 
African regiqn. 
