NATATORES. 513 



The lengthened hair-like plumes which ornament the face 

 are doubtless merely assumed during the breeding-season, for 

 I have frequently observed specimens in which this character 

 was wholly absent, and not unfrequently others in which it 

 was only partially developed. 



The sexes are both adorned with the plumes on the head, 

 and are moreover so nearly alike both in size and in colour 

 that dissection is necessary to distinguish them. 



In the breeding-season the head is black, with the forehead 

 and sides of the face beset with long fine hair-like white 

 plumes ; all the upper surface and wings brown ; base of the 

 primaries and the whole of the secondaries white ; under sur- 

 face silvery grey, tinged with brown on the flanks ; bill olive- 

 black with the tip white ; irides blackish olive with a very 

 fine circle of yellow near the pupil, and the olive beautifully 

 marked with a darker tint resembling lace-work ; lores red- 

 dish flesh-colour ; feet olive, tinged with yellow on the inner 

 side. 



After the breeding-season is over the head becomes brown, 

 the white plumes disappear, and the throat becomes bufl". 



Sp. 667. PODICEPS GULARIS, Gould. 



Black-throated Grebe. 



Podiceps dominicus, var., Lath. 



gularis, Gould in Proc. of Zool. Soc, part iv. p. 145. 



Tachtjbaj)tus gularis, Bonap. Compt. Rend, de FAcad. Sci., 1856. 

 Ung-bu -r-wa, Aborigines of Port Essington. 



Podiceps gularis, Gould, Birds of Australia, foL, vol. vii. pi. 81. 



This Grebe is very generally dispersed over the whole of 

 the southern portion of Australia, where it inhabits the 

 mouths of the larger rivers as well as the lagoons of the 

 interior, its numbers being much augmented during those 

 seasons of rain which too unfrequently occur in those por- 

 tions of Australia in which our possessions have been chosen. 



VOL. II. 2 L 



