BIRDS— COLOR AND NIDIFICATION. 455 



male -whilst almost a nestling, moults his soft brown plumage and 

 becomes of a uniform glossy greenish-black; but the female re- 

 tains for a long time the white striae and spots on the axillary 

 feathers; and does not completely assume the uniform black 

 color of the male for three years. The same excellent observer 

 remarks that in the spring of the second year the female spoon- 

 bill (Platalea) of China resembles the male of the first year, and 

 that apparently it is not until the third spring that she acquires 

 the same adult plumage as that possessed by the male at a much 

 earlier age. The female Bombycilla carolinensis differs very 

 little from the male, but the appendages, which like beads of red 

 sealing-wax ornament the wing-feathers,°° are not developed in 

 her so early in life as in the male. In the male of an Indian par- 

 rakeet (Palseornis Javanicus) the upper mandible is coral-red from 

 his earliest youth, but in the female, as Mr. Blyth has observed 

 with caged and wild birds, it is at first black and does not be- 

 come red until the bird is at least a year old, at which age the 

 sexes resemble each other in all respects. Both sexes of the wild 

 turkey are ultimately furnished with a tuft of bristles on the 

 breast, but in two-year-old birds the tuft is about four inches long 

 in the male and hardly apparent in the female; when, however, 

 the latter has reached her fourth year, it is from four to five inches 

 in length.''^ 



These cases must not be confounded with those where diseased 

 or old females abnormally assume masculine characters, nor with 

 those where fertile females, whilst young, acquire the characters 

 of the male, through variation or some unknown cause.^= But all 

 these cases have so much in common that they depend, according 

 to the hypothesis of pangenesis, on gemmules derived from each 

 part of the male being present, though latent, in the female; 



™ When the male courts the female, these ornaments are vibrated, 

 and "are shown off to great advantag'e," on the outstretched wings: 

 A. Leith Adams, 'Field and Forest Rambles,' 1873, p. 153. 



^1 On Ardetta, Translation of Cuvier's 'Regne Animal,' by Mr. Blyth, 

 footnote, p. 159. On the Peregrine Falcon, Mr. Blyth, in Charlesworth's 

 'Mag. of Nat. Hist.' vol. i. 1837, p. 304. On Dicrurus, 'Ibis,' 1863, p. 44. 

 On the Platalea, 'Ibis,' vol. vi. 1864, p. 366. On the Bombycilla, Audu- 

 bon's 'Ornitholog. Biography,' vol. i. p. 229. On the Palaeornis, see, 

 also, Jerdon, 'Birds of India,' vol. i. p. 263. On the wild turkey, Au- 

 dubon, ibid. vol. i. p. 15; but I hear from Judge Caton that in Illinois 

 the female very rarely acquires a tuft. Analogous cases with the 

 females of Petrocossyphus are given by Mr. R. B. Sharpe, 'Proc. 

 Zoolog. Soc' 1872, p. 496. 



=2 Of these latter cases Mr. Blyth has recorded (Translation of Cu- 

 vier's 'Regne Animal,' p. 158) various instances with Lanius, Ruticilla, 

 Linaria, and Anas. Audubon has also recorded a similar case ('Ornith 

 Bioff.' vol. V. p. 519) with Lyranga aestiva. 



