AVES FALCONID/C. 579 



black, connected with the neck-band on the sides ; the white area widens 

 to three inches on the upper breast, the black border extending well down 

 and defining the upper abdomen. The rest of the under surface, including 

 the lower tail-coverts, the axillaries and under wing-coverts, pure white. 



Feet and tarsus deep yellow ; the soles shaded with dull brown. 



Iris hazel-brown. 



Bill deep yellow, with a shading of blue close to the cere. Cere and 

 naked skin of forehead and lower mandibles orange, with a strong shading 

 of carmine. 



Geographical Range. — Province of Chubut, Patagonia. 



This carrion hawk, apparently heretofore undescribed, was received 

 in an exchange of bird-skins from the Museo La Plata; the bird is 

 undoubtedly fully adult, is a male, and was collected in Chubut in Feb- 

 ruary, 1896. It was catalogued in the collection of birds referred to 

 above as No. 8 and labelled Ibyder americarms, but evidently is from a 

 region where that species has not been obtained, and is thrown out of the 

 americanus group by the difference of the coloring of the underparts and 

 of the tail. Ibycter megalopterus has not been referred thus far to the ter- 

 ritory in which this seemingly new bird was collected ; nor does the color- 

 ing of the under parts seem to warrant the possibility that this is an 

 unknown plumage of megalopterus. The conspicuous necklace of black 

 crossing the pure white of the neck of this bird distinguishes it at once, in 

 the adult plumage, from any of its allies.^ 



Ibycter australis (Gmelin). 



Statenland Eagle, Lath. Gen. Syn. I. p. 40 (1781). 



Falco australis, Cm. Syst. Nat. I. p. 259 (1788: ex Lath.). 



Morplmtts novcB-zealandicE, Cuv. R^gn. Anim. I. p. 318 (181 7). 



Falco novcs-sealandice, Temm. PI. Col. I. pis. 192, 224 (1823). 



Polyborus novce-zealandice, Vig. Zool. Journ. I. p. 336 (1824); Darw. 

 Journ. Voy. Advent. & Beagle, p. 66 (1829); id. Natural. Voy. 

 Beagle, p. 57 (1882: Falkland Islands). 



Caracara novcE-zealandice, Less. Voy. Coq. Zool. I. p. 615 (1826: Falk- 

 land Islands). 



1 While it is impossible to decide positively upon the status of this species, I strongly suspect 

 that it will prove to be nothing more than /. albogularis, with remains of the immature plumage 

 on the neck and breast. — Witmer Stone. 



