190 Mr. H. Durnford on the Birds of 



be modified, as I have since found freshwater moUusks in 

 their stomachs. All I have shot have a strong, oflFensive smell. 

 Iris light reddish brown. Common at Baradero in April in 

 large flocks. 



94. Theristicus melanopis (Gm.). 



Ibis albicollis, Burm. La Plata-Reise, ii. p. 510. 



A winter visitor, arriving in May and leaving in October. 

 I have not observed it north of this city. Its long, curved 

 beak suggests an affinity to the Curlew ; but I have never seen 

 it except on comparatively dry ground, and its habits are 

 quite different from theirs. It is usually found in small 

 parties, whose harsh cries can be heard at a great distance. 

 Its flight is easy and powerful, and generally performed at a 

 considerable height in the air. It feeds on grubs and large 

 worms. 



95. Platalea ajaja, Linn. ; Scl. et Salv. P. Z. S. 1869, 

 p. 145. 



A winter visitor, going in flocks. Feeds on soft-bodied water- 

 insects and grubs. Generally distributed. A few at Bara- 

 dero in April. 



96. Chauna chavaria (Linn.) ; Scl. et Salv. Nom. p. 128. 

 Resident and very common. The breeding-habits of this 



species are curious. On the 24th June (our midwinter) I 

 was shooting with a friend, who found a nest containing eggs ; 

 and on the 28th the same thing happened again in a different 

 place. On the latter occasion the bird was seen to leave the 

 nest. One egg taken is exactly like some I obtained last 

 October^. The nest is a massive structure of reeds, about two 

 feet in diameter, and from one to two feet in thickness. The 

 bottom of the nest is always in the water. Common at Ba- 

 radero in April. 



97. Bernicla poLiocEPHALA, Scl. ct Salv. P. Z. S. 1876, 

 p. 366. 



Common in winter about fifty miles to the south of the 



[* We hope INIr. Dm-nford will forward to England some specimens of 

 the egg of Chauna, as they might assist in explaining the enigma of its 

 correct position in tlie natm'al series. — Edd.] 



