The Tanganyika Problem. An Account of the Researches Undertaken concerning the Existence of Marine Animals in Central Africa

THE TANGANYIKAPROBLEM.brought back from these lakes at all resembling the peculiar Tanganyika forms.On the other hand, the missionaries acquired further samples of shells from Tanganyika itself, and among these collections there were forms at once so strikingly different from those of any other known freshwater lake, and so curiously marine in aspect, that when describing them Mr. Smith* drew attention to the possibility that they might eventually turn out to be relics of some former sea.But whatever interest and curiosity may thus have been raised respecting the nature of these Tanganyika molluscs was suddenly and completely eclipsed by the announcement of the further discovery of jelly-fishes in the lake by the German traveller, Dr. Bohm.Their existence in WVanganyales was subsequently confirmed by Von Wissmann, and _ it can,-in fact, be said that it was only after theseannouncements that what I have termed the Tanganyika problem, as such, fairly took wing.The intensification of the general interest in the fauna of the African lakes which this discovery of jelly-fishes naturally produced, is not however far to seek, for if we except the star-fishes and seaurchins there is hardly any invertebrate type more typically marine, more characteristic of the ocean, than a jelly-fish.» Like herrings, the presence of jelly-fishes in fresh-water is indicative of the past or present connection of such water with the sea.|Béhm's discovery thus in fact seemed toshow, that either in present or past times, organisms like jelly-fishes could get from the sea into the lake.Eventually, through the co-operation of Mr. Frederick Moir and Mr. Swann, some of these medusze were sent to England, and on examination were found to be quite unlike any * FE

Geography · African history and culture studies