208 SEXUAL SELECTION: BIRDS. [Part II. 



adults at all seasons. We have an instance of the first of 

 these four cases in one of the egrets of India {fiuphus 

 coromandus), in which the young and the adults of both 

 sexes are white during the winter, the adults becoming 

 golden-buff during the summer. A\5ith the Gaper (Anas- 

 tomus oscitans) of India we have a similar case, but the 

 colors are reversed ; for the young and the adults of both 

 sexes are gray and black during the winter, the adults be- 

 coming white during the summer. 43 As an instance of the 

 second case, the young of the razor-bill (Alea toi'da, 

 Linn.), in an early state of plumage, are colored like the 

 adults during the summer ; and the young of the white- 

 crowned sparrow of North America {Fringilla leuco- 

 phrys), as soon .as fledged, have elegant white stripes on 

 their heads, which are lost by the young and the old dur- 

 ing the winter. 44 With respect to the third case, namely, 

 that of the young having an intermediate character be- 

 tween the summer and winter adult plumages, Yarrell " 

 insists that this occurs with many waders. Lastly, in re- 

 gard to the young differing greatly from both sexes in 

 their adult summer and winter plumages, this occurs with 

 some herons and egrets of North America and India — the 

 young alone being white. 



I will make only a few remarks on these complicated 

 cases. When the young resemble the female in her sum- 

 mer dress, or the adults of both sexes in their winter 

 dress, the cases differ from those given under Classes I. 

 and III. only in the characters originally acquired by the 



43 I am indebted to Mr. Blyth for information in regard to the 

 Baphus: see also Jerdon, 'Birds of India,' vol. iii. p. 749. On the 

 Anastomas, see Blyth, in 'Ibis,' 1867, p. 173. 



44 On the Alca, see Macgillivray, ' Hist. Brit. Birds,' vol. v. p. 347 

 On the Fringilla leucophrys, Aadabon, ibid. vol. ii. p. 89. I shall have 

 hereafter to refer to the yoang of certain herons and egrets being white, 



45 'History of British Birds,' vol. i. 1839, p. 159. 



