& 



i 7 2 SOME ETHIOPIAN REPTILES, FISHES, AND INVERTEBRATES 



where they exude a copious slime which causes the mud to form a kind of case 

 round the curled-up bodies. In such mud-nests these fishes have been transported 

 to Europe in a torpid condition. 



The third peculiar group is that of the beaked fishes, or Mormyridce, to which 

 reference has been made in the first chapter of this volume. These, like all the 

 fishes noticed below, belong to the great bony group, and are specially characterised 

 by the elongation of the almost trunk-like muzzle, the length and shape of which 

 varies in the different genera. It is a remarkable fact that these peculiar beaked 

 fishes, so eminently characteristic of the fresh waters of Ethiopian Africa 

 o-enerally, are unrepresented in Lake Tanganyika. Another peculiarity in the fish- 

 fauna of that lake is the occurrence of a representative of the Asiatic cyprinoid 

 genus Capoeta, known elsewhere in Africa only by a single Abyssinian species. 



Some interesting observations on the habits of beaked fishes have been made 

 in the Zoological Gardens at Giza, near Cairo. In a natural state all these fishes 

 appear to be thoroughly nocturnal, but in captivity they soon learn to move about 

 during the daytime, when they will search for the chopped worms on which they 

 are fed. Specimens of the long-nosed species known as Mormyrus kannume 

 generally spend the day lying quietly at the bottom of the tank, but after nightfall 

 become very active, searching energetically after food. When a light is thrown 

 on them, their eyes shine in a very remarkable manner, sometimes shining white 

 and sometimes gleaming red. They have also a curious habit of swimming tail- 

 first. There are many genera and species of these fishes, among which the one 

 mentioned above and Gymnarchus niloticus of the Nile and the west coast rivers 

 are two of the best known. 



Among other fishes, the occurrence of a species of the southern genus Galaxias 

 in the rivers of Cape Colony cannot be passed over without notice, as other species 

 occur in South America and Australia, and the genus has accordingly been regarded 

 as adding to the evidence in favour of a former land-connection between the 

 southern continents. In this instance the evidence has, however, been consider- 

 ably discounted by the discovery of a marine Galaxias. 



Cat-fishes of the family Sihvridce abound in the Ethiopian region, among these 

 being the carmut, or eel-like cat-fish (Clarias angiullaris) of the Nile and other 

 rivers. About a yard in length, this fish, which belongs to a genus common to 

 Africa and India, is frequently taken when the water is low. The electric cat- 

 fishes, as typified by Malapterurus electricus, are peculiar to African waters. The 

 ishr or so-called Nile perch {hates niloticus), of the family Serranidce, has been 

 referred to in Chapter I. According to observations made at Giza, the natural 

 food of these monsters appears to be live fish only, but they will eat freshly dead 

 fish thrown into the tanks, seizing them as they sink and swallowing them whole. 

 One of the most noticeable points about the ishr is its gleaming eyes, which in 

 some lights glow red like dull signal lamps ; another is its power of rapidly 

 changing colour, and the appearance and disappearance of dark markings all over 

 the sides of the body. The carp family (Cyprinidce) is strongly represented in 

 African waters, especially by barbels (Barbus), of which nearly two hundred 

 species are known to inhabit Africa. As no remains of the Cyprinidce have 

 hitherto been recorded from the Tertiary formations of the Fayum district of 



