32 Mr. E. Gibson on the Or?ti(/ioIo(/i/ of [Ibis, 



Rosy-billed Duck, in front and at the !>ides of which there 

 swam no less than fifty-two young, all small, no other duck 

 being in the vicinity. On 20 November and 9 December, 

 1915, one of my collectors took two nests, each containing 

 ten slightly incubated eggs ; these nests were constructed 

 of dry flags in a covert of the same. 



I should describe the eggs as the roundest of all the duck 

 tribe, though closely approached by those of the Fulvous 

 Tree-Duck [Bendrocygna fulva Gm.). Tiiey are of a buff- 

 colour, and average 59x45 mm. 



355. Erisniatura ferruginea Eyton. Rusty Lake-Duck. 



Of the Rusty Lake-Duck it may be said that its occvir- 

 rence in our district is less uncommon than elusive. Claude 

 Grant correctly summarises the situation when he states 

 that " this Duck is not commonly observed in the Ajo 

 district, where it frequents the open water surrounded by 

 ree;ls. On being alarmed it dives after the manner of a 

 Grebe, and I have never seen it take to the wing. When 

 swimming, the tail is held upright and the body lies very 

 low in the water, which almost closes over the shoulders^' 

 ('Ibis,' April 1911, p. 850). 



I have frequently come across a pair of these Ducks, either 

 wdien noisily forcing my way through the rushes on horse- 

 back, or moving quietly along an open channel in a catioe, 

 on emerging into an open lagoon in the deeper and moie 

 solitary swamps. Watchful, sombre, silent, and shy, they are 

 observant for a moment or two, then seem to settle lower 

 down in the water in an almost imperceptible manner, and 

 finally vanish below the surface and gain the shelter of 

 the reeds. Their dive to the flash of a gun is generally 

 successful; and, in a word, their liabits are evasive in the 

 extreme. Mr. Hudson's bi'ief notes are also corroborative 

 of these peculiarities. 



Under such circumstances it is natural to assume that the 

 possible discovery of a nest is due only to mere chance or a 

 most diligent seai'ch. I herewith put upon record such 

 few instances as have come under mv notice. In 1875 I was 



