after heading it ofT into small creeks along the banks. Contrarily, other characins like Disli- 

 cliodus are small, graceful creatures with an elongated body striped with long black bands. 

 They browse among the reeds. 



In the clear waters of the Congo swims a fine cyprinid, the biriki (Barbiis tropidolepis). 

 Like a salmon, it leaps in the waterfalls and torrents. This species, which may exceed three 

 feet in length, has a first-rate flesh and is intensively fished. 



Mormyrids and cichlids are still found at the equator, the latter fishes being particularly 

 abundant in Lake Tanganyika. The mbu (Teiraodon mbii), a puffer-fish closely related to 

 the Nile species, often floats at the surface in a quite distended state. Unfortunately, it may 

 be spotted by young Congo natives, who use the poor animal for a football match and then 

 throw it back into the river where it deflates with all possible speed so that it may sink and 

 recover from its emotion. Along the banks, a small greenish, silvery fish sometimes rises into 

 the wind to glide with its outspread pink-coloured fins. It is the chisel-jaw (Paniodon), and 

 was first observed by M. de Brazza. 



Because of its constant climatic conditions, the nature of its soil and also because of the 

 difficulty of penetrating its interior, which hinders the ravages of so-called civilised people, 

 the African continent is peculiar in retaining animal species that may have disappeared elsewhere. 

 It is the " chosen land " of " living fossils "; elephants, giraffes, aard-varks, okapis and other 

 mammals, without counting the last descendants of old human races. These still manage to 

 survive in the dense forest or in the savannahs, shielded from the hunting or colonising incursions 

 of the so-called pioneers of European progress. 



In the aquatic province it is much the same. In sight of hippopotamuses and crocodiles 

 there remain a few fishes that have disappeared elsewhere. The laichirs (Polyplenis) were the 

 last known crossopterygians before the recent discovery of the coelacanth. The species of 

 Prolopierus are among the last of the lung-fishes and the osteoglossids are archaic teleosts. The 

 bichirs, (Polyplerus bichir), which survive in the basins of the Nile, Niger and Congo, have a 

 very long body armed with oblique rows of shining lozenge-shaped scales. Along the back the 

 fin is broken into a series of discrete spines, followed by some soft rays. These fishes remain 

 motionless on the mud, the head raised and propped up by the lobed pectoral fins. When 

 the water is very stagnant they swim to the surface to gulp pure air. The spawn is laid on the 

 underwater banks and out of the eggs come attractive looking fry with black and golden stripes. 

 They bear long, feathery external pink gills which disappear at the end of development. 



Devonian fishes used to live in marshes at the boundaries of red-sand deserts. But the 

 heat of the very warm summers completely dried up the mud in which they were buried in 

 their search for cool surroundings. Deprived of water, they became adapted to these hostile 

 natural conditions. Their swim-bladder became a lung and so they were able to breathe in 

 oxygen directly with the air. These fishes with two ways of respiration are lung-fishes and 

 one representative of this group in Africa is Prolopierus annedens. During the rainy season it 

 is active, hunting for frogs, crustaceans and worms, and fighting with members of its own kind. 

 But at the dry season, when the waters are beginning to disappear, it hollows out a burrow 

 in the mud. It rolls itself up in this hole, and glands in the skin secrete a mucus, which is 

 made into a cocoon, with a single opening to which the lips of the fish are applied. In this way 

 it remains motionless for several months in a state of suspended animation, slowly digesting 

 its accumulation of fat reserves. When the waters once again invade the swamps, the lung- 

 fish leaves its protective cocoon and begins to experience the irresistible urges of the breeding 

 season. The eggs, which are laid in a hole in the mud, are guarded by the males, who have made 

 a small hidden exit at the bottom of the nest, through which they can escape amid the reed 

 beds without attracting the attentions of predators, avid to gobble up the brood. The young 

 fishes look like salamander tadpoles with feathery, pink, external gills. During the daytime 

 their colouration blends with that of the mud but at night they become transparent and invis- 

 ible through the contraction of their colour cefis. After a month in the nest the fry lose their 

 external gills and acquire a lung through the transformation of the swim-bladder. The habits 

 of all these African fishes have been studied by the English scientist .1. S. Budgett. 



Large osteoglossids (Helerolis nihlicus) swim ponderously in the neighbourhood of the 



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