32 THE ANIMALS OF NORTHERN AFRICA 



the scarcity of ostriches, and steps were taken to recruit their numbers. These, 

 however, did not prove successful ; but an attempt to retrieve this lack of success 

 was made in 1908 by the Algerian Government, who decided to establish a farm 

 in the district of Jebel Nador, about 135 kilometres south of Tiaret, where 

 wild ostriches were formerly numerous. As none were obtainable in the neigh- 

 bourhood, five ostriches were bought in Abyssinia and transported to the park, 

 where they arrived safely ; but unfortunately the experiment has hitherto proved 

 practically a failure. 



„ „ „ , While so many of the North African mammals and birds are of a 



Soft Tortoise. J 



South European type, a large proportion of the reptiles have no repre- 

 sentatives in Europe. The curious soft river-tortoise (Trionyx triv/agvAs) is one 

 of these non-European types, which belongs to a widely spread genus and family, 

 and also occurs in western Africa. When the head and neck are protruded 

 this tortoise measures about a yard in length from muzzle to tail-tip. In colour it 

 is greenish or brownish above, ornamented with white spots, and dull white 

 beneath. It is known to the Arabs as tirsen ; and its flesh is edible. As its 

 American relative devours young alligators, so the African species feeds on baby 

 crocodiles as they issue from the egg ; also consuming water-fowl, frogs, insects, 

 and other creatures. 



Northern Africa is the home of the typical and longest-known 

 member of the crocodilian order, the tinisa of the Egyptians, and the 

 Nile crocodile (Crocodilus niloticus) of naturalists. This species, which is now 

 unknown to the northward of Thebes, occurs not only in the Nile, but in the rivers 

 of East and South Africa, as well as in Madagascar. Even in the upper Nile the 

 crocodile nowadays seldom exceeds 18 feet in length, although a few reach 20 or 

 even more feet. Some individuals have broader muzzles than others, and the 

 form of the whole head shows such a remarkable difference that there would at 

 first sight seem to be two distinct races of the species. Specimens are, however, 

 met with which completely bridge over the difference between the extreme types. 



In the Atbara River and the Blue Nile, crocodiles attack not only domesticated 

 animals, such as goats, sheep, and dogs when they come down to drink, but also 

 natives who may be bathing in or fetching water from the river. On such 

 occasions these reptiles approach the shore by drifting slowly on the surface of the 

 water, when they look like the trunks of old trees ; no sooner, however, are they 

 sufficiently close than they suddenly rise, knock down their victims with a blow 

 of their tails or by a snap of their huge jaws, and then drag them into deep water. 

 One instance is related, supported by photographs of the actual scene, where a 

 rhinoceros, while crossing a river in East Africa, was seized by one hind-leg by a 

 crocodile and after a somewhat protracted struggle eventually drawn backwards 

 into the water and drowned. After death the prey is dragged to some other part 

 of the shore to be devoured at leisure. In Sennar, the women who fetch water are 

 in the habit of beating the surface of the river with sticks, and keep constantly on 

 the look-out, for the slightest carelessness may be fatal, as a crocodile may swim 

 up unnoticed under the surface of the water, and measure the distance so exactly 

 that it will seize one of the party at the first attempt. On one occasion an English 

 traveller watched an unusually large crocodile lying immovable like a log between 



