578 PATAGONIAN EXPEDITIONS ! ZOOLOGY. 



Ibycter circumcinctus Scott. 

 Ibycter ctrcumct'ncfus Scoit, Auk, XXVII, p. 152, 1910. 



Type. — Princeton University Collection, 8993. Adult male. Chubut, 

 Patagonia, February, 1896. Collected by the Museo de la Plata. (Orig- 

 inal Number 8; exchange with Princeton University.) 



She. — Male cited. 



Total length, about 24 inches. 



Wing, 16.25 inches. 



Culmen, from in front of cere, 1.30. Cere at forehead, 0.40. 



Tail, 10.30 inches. 



Tarsus, 2.55 inches. 



Color. — General color : Black and white. Black preponderating above ; 

 white prevailing below. 



Head : Black with lanceolate feathers, prolonged on the occiput into a 

 decided occipital crest ; undershading throughout deep brown. 



Neck: Black above and on the sides, with deep brown undershade. 

 Chin and upper neck below pure white ; this is divided from the white 

 lower neck by a black band, more or less variegated with white markings 

 on some of the feathers ; this band is an inch and a half wide. Lower 

 neck white, with the black of the sides confining it to a narrow strip, which 

 widens on the upper breast. 



Back : Mantle and lower back black with a dull green gloss and under- 

 shade of deep brown. Rump and upper tail-coverts pure white. 



Tail : The base definitely white, the rectrices here having ivory-white 

 shafts ; thence black prevails for six inches and the shafts of the rectrices 

 are shining black ; a terminal pure white band about an inch and a half 

 broad, and here the shafts of the rectrices are again ivory-white. Below, 

 the tail is duller, but presents the same pattern. 



Wings : Above black, with a dull brown undertone, obscure and green 

 reflections ; the quills black, both the primaries and secondaries tipped 

 with white. Small plumes along bend of wing conspicuously white, when 

 wing is closed ; the feathers of the border of the shoulders first white, then 

 chiefly black, with an admixture of white, and finally wholly black. 



Under parts: The chin and throat white, separated from the white of 

 the breast by a broad black band, somewhat variegated with white mark- 

 ings, irregular in shape and size, on some of the feathers. The white on 

 the lower throat is confined to a narrow strip in the center, bounded by 



