26 FROM THE NIGER TO THE NILE 



water. When studpng the remarkable blade-like shape, it is 

 difficult to imagine it serving any other purpose than prising 

 open shells or scraping of! molluscs from stones. I have 

 taken the eggs of this species on sand-banks in the Zambesi. 

 A hole scratched in the sand serves as the nest, and in colour 

 and markings the eggs resemble those of our common tern. 



During the dry season when the water is low, the view 

 across the river is often interrupted by stretches of sand- 

 banks and small islands covered with tall reeds and fish cane, 

 frequently forming snug backwaters that become the night 

 .sanctuaries of many birds. A locality such as this is a 

 favourite home of the lark-heeled cuckoo {Centropus sene- 

 galensis), a rather remarkable bird that is to be found in the 

 vicinity of most African rivers. It is about the size of a 

 falcon, with upper part of a reddish brown and the under 

 a dull white, and a tail powerful and big for its size. 

 It seldom makes use of flight except to wing its way in a 

 clumsy, flopping manner from one thick retreat to another, 

 where at times it gives out a string of rich bubbling notes. 

 The best time to observe this bird is towards sunset, and 

 from an ambush near the water one can watch it almost as 

 closely as one likes. First, one sees troops of doves come 

 down to the pools and take their last drink, and batches of 

 weavers pitch into the reeds with rustling flight for the 

 night. Then comes a brief stillness, to be broken shortly by 

 a creepy noise in the reeds, a tusshng sound as of roots and 

 thick growth being pulled aside. It is the cuckoo working 

 its way in rodent fashion through the columns of the reeds. 

 On emerging into the open it does not neglect to reconnoitre 

 and climbs cautiously up one of the stoutest fish canes over- 



