ANSERES ALOPOCHEN 127 



Length about 19-5 ; wing 9'5 ; tail 2-0 ; culmen 2-0 ; tarsus 2-0. 



The sexes are alike ; young birds have very little maroon on the 

 lesser wing-coverts, the under parts paler and the upper tail-coverts 

 margined with brown. 



Distribution. The Whistling -Duck has a very remarkable dis- 

 connected range, extending over four continents ; it is met with in 

 the southern part of the United States and Mexico in North 

 America, from Venezuela and Peru to the Argentine in South 

 America, from Kordofan southwards along the Nile Valley, through 

 Nyasaland, to Lake Ngami in Africa, in Madagascar, and finally in 

 India, Ceylon and Burma. 



The first notice of its occurrence within our limits is that of 

 Holub, who obtained from Walsh a specimen shot at Sesheke on 

 the Upper Zambesi in the month of January ; there is a pair in 

 the South African Museum obtained by Mr. Eriksson, the one 

 labelled Botletli Kiver, July, 1885, the other, Tebra Country, near 

 Lake Ngami, April, 1884, while the German traveller, Fleck, also 

 brought an example from Lake Ngami, shot in August. Mr. A. D. 

 Millar tells me that there is an example of this species in the Durban 

 Museum, obtained by himself in that neighbourhood some years ago. 



Genus V. ALOPOCHEN. 



Type. 

 Chenalopex, Stephens (nee VieilL), Gen. Zool. xii. 



pt. 2, p. 41 (1824) A. aegyptiacus. 



Alopochen, Stejn., Standard Nat. Hint. iv. p. 141 



(1885) A. aegyptiacus. 



Bill stout, short and deep, its depth at the base about half the 

 length of the culmen ; no prominent lamellae at the edges of the 

 bill ; nostrils oval ; wing long and pointed, reaching nearly to the end 

 of the tail, a metallic speculum formed by the secondaries in front, 

 a blunt osseous callosity at the bend of the wing ; tail of fourteen 

 feathers, broad and square ; tarsus long and strong, considerably 

 exceeding all the toes, with a narrow line of transverse scutes 

 in front ; hind toe with a narrow lobe ; an osseous bulb at the base 

 of the trachea in the male. 



This genus contains two species only the type here described 

 and A. jubatus from tropical South America. 



