TRANSACTIONS OF SECTION D. 419 
The exclusively fresh-water Silurids now found in Africa are all geterically 
distinct from the South American forms, whilst the West African species that 
enter the sea belong to the same genus (Arius). This consideration seems to me 
o speak against any continental extension across the Atlantic later than the 
earliest Tertiary times, and so does the fact that the Middle Eocene forms found 
in Egypt,and recently described by Dr. Stromer, differ so little from their existing 
representatives, Bagrus and allies. On the assumption of a late Eocene or Miocene 
Atlantic, we should expect to find a much closer relationship between the 
American and African strictly fresh-water fishes than exists at the present day, 
whereas only those forms that are known to enter the sea are generically identical 
in those two parts of the world. 
The two exclusively fresh-water Silurids found in Madagascar show closer 
aflinity with the African than with the Indian forms, and may have immigrated 
from Africa in the early Tertiary times through the bridge which then existed, 
unless they have been derived from marine types, which is quite possible. 
THE GALAxiID#.—Two small fishes originally described by F. de Castelnau as 
Loaches, and now referred to Galaxias, occur on the flats near Cape Town and in 
the Lorenz River, some twelve miles from its mouth in False Bay. They are of 
special interest as belonging to a family and genus long believed to be exclusively 
confined to fresh waters and characteristic of the extreme south of America, New 
Zealand, and Southern Australia. After Dr. Steindachner had first recognised 
the true affinities of the Cape species, Professor Max Weber was inclined to regard 
this interesting discovery as affording a new argument in favour of the past 
antarctic continent on which so much has been written. But Dr. Wallace was 
nearer the truth when he suggested that a land connection within the period of 
existence of one species of fish, viz., Galaxtas attenuatus, known from Chili, 
Patagonia, Tierra del Fuego, the Falkland Islands, New Zealand, and Southern 
Australia, would have led to much more numerous and important cases of 
similarity of natural productions than we actually find, and that we must rather 
look to the transport of the ova across the southern sea to explain this very 
remarkable distribution. A betteracquaintance with the Galaxias has confirmed 
Dr. Wallace’s supposition, as it is now an established fact that some species live 
in the sea. G. attenuatus has been observed in the Falkland Islands and in New 
Zealand to descend periodically to the sea for the purpose of spawning. No 
doubt the early Galaxias lived in the sea, and the Cape species, like many others, 
only afford examples of ori-inally marine forms having settled in fresh waters. 
Curiously, at the other extremity of Africa the same thing has happened in the 
case of several small fishes pertaining to three different families—the Gobiide 
the Blenniide, and the Syngnathide—to say nothing of such types as the Trout 
and the Stickleback, the presence of which in Algeria, were it not proved that land 
communication between Southern Europe and North-West Africa existed up to 
very recent times, could be accounted for by a direct marine ancestry, as shown 
by their nearest relations. 
As the early Tertiary ‘ Antarctica, as designed by Professor H. F. Osborn 
does not involve South Africa, the presence of species of Galaxias at the Cape 
cannot, even on that hypothesis of continental extension, be explained except on 
the assumption of their marine origin. 
Tue Kyeriipa.—A monotypic family with two species, one from Angola, 
the other from East Africa. These little fishes are related to the Pikes, Esocide ; 
and there is no reason that I can see against their being possibly derived from them, 
in which case they would be of northern origin, the Zsocide, now confined to the 
northern hemisphere, being known from fresh-water deposits in Europe as far 
back as the Oligocene, 
Tue Cyprinopontipa:.—The members of this large family are mostly Central 
and South American. They are comparatively few in Africa, but have represen- 
tatives in every part, and also in Madagascar and the other islands of the Indian 
Ocean. Although principally restricted to fresh waters, not a few species are 
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