252 



THE BIRDS OF RIVER AND VLEI 



freckling, and has the lower surface mottled with white 

 and brown. Length, 20 inches. 



It is fairly generally distributed over South Africa. It 

 arrives at Modderfontein in August, leaving again in April. 

 The eggs are pale creamy- white. 



The White-backed Duck (Thalassornis leuconotus) is widely 

 spread throughout the sub-continent. The top of the head 

 and the throat are black ; above and below of a yellowish- 

 brown colour mottled and barred with black ; centre of 



Fig. 140. — Nest and eggs of White-backed Duck. (Photo. Haagner.) 



back pure white. Bill, short and stumpy, and of a blue 

 and slate colour. Length, 17 inches. 



Within our limits it is widely distributed, but remains 

 so far unrecorded from Ehodesia. It is an expert diver, 

 and seldom flies, although it can and does fly when perse- 

 cuted. It rests in the water, amongst the weeds, with 

 the whole body submerged, only the top of the head as 

 far as the eyes and the bill being exposed, which is all 

 the mark usually available to aim at. They are not bad 

 eating at times, although somewhat oily. The nest is a 

 saucer of sedge, rushes and weeds, built on the beaten-down 

 weeds growing in the water, and is usually well concealed. 



