AVES ARDEID/E. 379 



Immature birds are much shaded with brown, the blue black areas all 

 more or less defined in dusky brownish. The effect of the lower parts is 

 striped brownish and white, without the defined black areas. They lack 

 entirely the drooping pendant plumes of adults. 



Geographical Range. — The whole of South America to the Straits of 

 Magellan. 



The Cocoi Heron was not obtained, though recorded, by the naturalists 

 of the Princeton Expeditions. An individual cited, in the Princeton Uni- 

 versity Museum and the series of birds of this kind in the British Museum, 

 are the basis for the descriptions furnished. The birds do not appear to be 

 abundant anywhere in Patagonia and are somewhat local in their distri- 

 bution. They have been noticed as resident and as especially common in 

 the winter, by Barrows in his series of papers cited, in lower Uruguay and 

 it seems probable that in Patagonia these herons are migrants, leaving for 

 the north during the colder months. 



"Female. Cosquin, Cordova, Arg. Rep., Sept. 23, 1882. 



"Iris amber. 



"• Ardea cocoi is by no means common here, as during my stay of five 

 months I only saw three or four. 



"Their usual position was, perched on a tree in early morning and not 

 far from the river." (E.W.White, P. Z. S. 1883, pp. 41-42.) 



Genus HERODIAS Boie. 



Type. 



Herodias, Boie, Isis, 1822, p. 559; Sharpe, Cat. Bds. Brit. 

 Mus. XXVI. p. 88 (1898); id. Hand-List I. p. 195 

 (1899) .......... H. egretta. 



Egretta, Bonap. Oss. Regna Anim. p. 97 (1830) . . . H. egretta. 



Casmerodius, Gloger, Handb. p. 412 (1842) . . . . H. egretta. 



Geographical Range. — Nearly cosmopolitan. 



Herodias egretta (Wilson). 



Le Heron Blanc (pt), Briss. Orn. V. p. 428 (1760). 



La Grande Aigrette d'Amerique, D'Aubent. PI. Enl. VIII. pi. 925 (1780). 



La Grande Aigrette, Buff. Hist. Nat. Ois. VII. p. 377 (1780). 



Great Egret, Lath. Gen. Syn. III. pt. i. p. 89 (1785). 



