1914] Beebe : Ontogeny of the White Ibis. 247 



tinual observation. The appearance of such asymmetrically 

 pigmented feathers would seem to lend credence to such color- 

 change, but in every case where my clipped and threaded ob- 

 servation feathers were scrutinized, there was no infiltration or 

 even local wearing or change in area of pigmentation whatso- 

 ever. The variation in the juvenile feathers of the White Ibis is 

 congenital, not transitory or ontogenetic. 



If feathers be plucked out from the wings of a two months' 

 old bird, the new growths which take their place differ little or 

 not at all from the original ones. In the third and fourth 

 months, however, much of the immature brown pigment is lost, 

 and from the sixth month onward the ingrowing feathers will be 

 pure white as in the adult. Normally these would not appear 

 for another six or eight months. In the five months' old bird 

 one can readily detect every vicious peck it has received from 

 other inmates of the cage, by the white feather or group of 

 feathers which marks the place of the others plucked out. 



In early spring, if one of the dull brownish outer primaries 

 be pulled out, there comes in a feather, not pure white, but with 

 the pigment strengthened and concentrated on the terminal half 

 and very strongly glossed with iridescent green. This is identi- 

 cal with what I found occurring in the intensified melanism 

 zones in wild doves. ^ 



Nothing definite seems to have been recorded in regard to 

 the annual change in color of the exposed soft parts of the adult 

 White Ibis. In mid-winter, the bill and face of the bird is of a 

 rich fleshy pink, evenly colored throughout. About Christmas 

 or the first of the year the first change is noticeable, which, 

 rather remarkably, is a paling of the color. The region about 

 the eye, the lores and the base of the bill for some 15 mm. from 

 the base, fades from pink, to pale pinkish white. The face and 

 the basal band on the bill, about mid-February, again increases 

 in color and gradually becomes intensified. The legs and feet 

 show no change but the cheeks, with their white feathering, 

 begin to be puffed out. A month later, well into March, the most 

 interesting change is a dark ring which appears around the mid- 

 dle of the beak about 75 mm. from the tip and spreads in both 



i Zoologica, Vol. T. No. 1, p. 31. 



