414, : REPORT—1905. 
comparing the present data with those to which Professor Gregory, on the faith 
of Dr. Ginther’s list, appealed to justify his theory of a direct connection in tke 
past of the Upper Nile with the Jordan through a river flowing along what is 
now the Red Sea. To this question we shall revert presently. 
Whilst the exploration of rivers and lakes has resulted in such a rich harvest, 
it remains a matter for serious regret that we should still be without any 
information as to the precursors of the African fishes. In spite of diligent search 
over a considerable portion of the great continent, no remains of any post- 
Triassic fishes have yet been discovered in Tropical and South Africa, and our 
acquaintance with Tertiary Teleosts generally is still almost as scanty and 
fragmentary as it was twenty years ago, although much has been done by Dr. Smith 
Woodward in elucidating the affinities of such remains as have been exhumed. 
Under the circumstances we have to fall back on our imagination to explain the 
origin of the most important groups characteristic of the present African fish- 
fauna, and much hazardous speculation has been indulged in. Thus, without 
any sort of evidence, the Cichlid Perches of Africa have been supposed to 
emanate from ancestors inhabiting hypothetical Jurassie or Cretaceous seas ex- 
tending over Central Africa, whilst connecting land areas have been too freely 
postulated to account for the resemblance between the fishes of Africa and 
Tropical America, and antarctic continents devised to explain the presence of 
Galaxias in South Africa. To these suggestions I shall refer further on when 
dealing with the distribution of the families to which they were intended to 
apply. Although it is highly desirable that zoologists should base their theories 
of geographical distribution upon geological data, I think we must regret the 
growing tendency to appeal to former extensions of land or sea without sufficient 
evidence, or even contrary to evidence, in order to explain away the riddles that 
offer themselves. 
Twenty-five years ago a list of the African fresh-water fishes would have in- 
cluded the names of about 350 species (Giinther gave the number as 255 only), 
some fifty of which have since lapsed into the synonymy, whilst at the present day 
we are acquainted with 976 species, referable to 185 genera and forty-three families. 
Of the latter five were then unknown, or unknown to have representatives in this 
part of the world. The forty-three families are here enumerated, with an indication 
of the number of genera and species according to the most recent census :-— 
CHONDROPTERYGII. OSTARIOPHYST, 
PLAGIOSTOMI, 14, Characinidey, 20, 93. 
15, Cyprinidze, 12, 202. 
1. Carchariide, 1, 1. 16. Siluride, 37, 187. 
2. Pristide, 1, 1. 
CROSSOPTERYGII. APODES. 
CLADISTIA. 17, Anguillidz, 1, 6. 
3. Polypteride, 2, 11. HAPLOMI, 
18. Galaxiide, 1, 2. 
DIPNEUSTI. 19, Kneriidee, 1, 2. 
4. Lepidosirenide, 1, 3. 20. Cyprinodontide, 5, 39. 
TELEOSTEI. eA och oe a 
MALACOPTERYGII. 22. pinleecries 2 3. 
. Elopide, 2, 3. 
PERCESOCES. 
. Notopteride, 2, 2. 
5 
6. Mormyridz, 11, 108. 
7 
8 
. Osteoglosside, 1, 1. 
23. Scombresocids, 1, 1. 
24. Atherinidez,, 2, 3. 
9. Pantodontide, 1, 1. 25. Mugilide, 2, 13. 
10. Phractolemide, 1, 1. 26. Polynemide, 3, 3, 
1). Clupeide, 6, 7, 27. Sphyreenide, 1, 1. 
12. Salmonidee, 1, 1. 28. Ophiocephalidz, 1, 3. 
13. Cromeriide, 1, 1. 29. Anabantide, 1, 14. 
