Note 265 — Chapter XVI

I have noticed the following cases in Audubon’s ‘Ornith. Biography. The Redstart of America’ (Muscicapa ruticilla, vol. i. p. 203). The Ibis tantalus takes four years to come to full maturity, but sometimes breeds in the second year (vol. iii. p. 133). The Grus Americanus takes the same time, but breeds before acquiring its full plumage (vol. iii. p. 211). The adults of Ardea cærulea are blue and the young white; and white, mottled, and mature blue birds may all be seen breeding together (vol. iv. p. 58): but Mr. Blyth informs me that certain herons apparently are dimorphic, for white and coloured individuals of the same age may be observed. The Harlequin duck (Anas histrionica, Linn.) takes three years to acquire its full plumage, though many birds breed in the second year (vol. iii. p. 614). The White-headed Eagle (Falco leucocephalus, vol. iii. p. 210) is likewise known to breed in its immature state. Some species of Oriolus (according to Mr. Blyth and Mr. Swinhoe, in ‘Ibis,’ July, 1863, p. 68) likewise breed before they attain their full plumage.