CROCODILES 247 



banks are white, gray, or crimson, from the solid masses 

 of birds, the most brilliant of which are the tantalus 

 ibises. By night these feathered crowds are constantly 

 'rushed' by the crocodiles, which during this season 

 live more on fowls than on fish. The incredible number 

 of the birds is maintained from two sources : part are 

 recruited by the migrants from Europe and Asia ; part 

 are native birds which have reared their young earlier, 

 and bring them to the river when the African Steppe is 

 too parched to yield food. Among these native birds is 

 the ' zic-zac,' which Herodotus called the trochilus. 

 Now, as then, it is the constant attendant of the 

 crocodile, and spends its whole life on the sandbanks, 

 which these monsters also haunt. Brehm not only 

 watched it feeding round the crocodiles, and even 

 prying into their open jaws as these creatures commonly 

 sleep with their mouth open and the lower jaw dropped 

 but also noted their extreme cunning in other respects. 

 At the season of low Nile the crocodile bird is more 

 constant to the sandbanks even than the crocodiles 

 themselves. The latter only use them to bask on by 

 day ; the birds sleep there and lay their eggs on the 

 sand. Brehm, though certain that they were nesting, 

 could not succeed in finding their eggs. One day he 

 saw a bird give two or three scratches with its feet before 

 it flew off the bank. He swept away the sand and found 

 that underneath it were the eggs. The crocodile bird, 



