CASARCA CANA. 753 
during the rainy season and the few months which follow, but was 
not seen during the dry, hot time. It feeds in fields and marshes, 
perching readily on trees. The flesh is good, more tender than 
that of the Black Goose, but without the delicate flavour of the 
Whistling Duck.” 
According to Mr. Andersson, “this very handsome species is 
common in Damara and Great Namaqua Land during the rainy 
season, and is found at all seasons at Lake N’gami and on the 
River Okavango. It is usually found in flocks, and may not 
unfrequently be seen perching on dry trees near the water; its 
flesh is very good.” Senor Anchieta has forwarded many specimens 
to the Lisbon Museum, procured at Caconda (native name Violo), 
Huilla, Gambos, and Humbe (native name Heubo). 
Upper parts, blackish-brown, shining-coppery on the back, and 
brilliant green on the wing; rump brownish-grey ; under parts 
whitish; flanks grey; head and neck white, covered with black 
spots, which form a broadish line from the top of the head, down 
the back of the neck. ‘he male, in the breeding season, has a 
large elevated flattened black caruncle extending down the centre 
of the upper mandible. Length, 24”; wing, 15"; tail, 7”. 
726. Casarca cana (Gm.). South African Shell-Duck. 
Oasarca rubida, Layard, B. 8. Afr. p. 350. 
The “ Berg-Hendt ” is readily distinguished by its rufous colour 
and grey head. It is rare in the colony, appearing at odd times in 
different places. We are told it breeds among rocks, and, like the 
Dendrocygna, conveys its young down to the water on its back. 
“Three specimens,” writes Mr, Ayres, “were killed by my 
brother on a lagoon in the Free State; but birds of this species 
also occur on this side the Vaal, where I have seen them, but have 
never been able to get at them.” 
General colour, rufous, inclining to yellow (fulvous) on the chest 
and vent, and mottled with minute wavy black lines on the back ; 
rump and lower part of back very dark grey ; tail black, shining 
green ; shoulder pure white ; green patch on the wing, very large ; 
head and neck ash-coloured, with a dark rufous collar. Length, 
2’ 3’; wing, 15”; tail, 63”. 
3 ¢ 
