BIRDS. 553 



tJie females alone. Or the young may have an intermediate 

 character; or, again, they may differ greatly from tJie adults in 

 both their seasonal plumages. The cases in this class are singularly- 

 complex; nor is this surprising, as they depend on inheritance, 

 limited in a greater or less degree in three different ways, namely, 

 by sex, age, and the season of the year. In some cases the 

 individuals of the same species pass through at least five distinct 

 states of plumage. With the species in which the male differs 

 from the female during the summer season alone, or, which is rarer, 

 during both seasons,* the young generally resemble the females 

 as with the so-called goldfinch of North America, and apparently 

 with the splendid Maluri of x\ustralia.f With those species, the 

 sexes of which are alike during both the summer and winter, the 

 young may resemble the adults, firstly, in their winter dress ; sec- 

 ondly, and this is of much rarer occurrence, in their summer dress ; 

 thirdly, they may be intermediate between these two states ; and, 

 fourthly, they may differ greatly from the. adults at all seasons. We 

 have an instance of the first of these four cases in one of the egrets 

 of India {Buphus coromandus), in which the young and the adults of 

 both sexes are white during the winter, the adults becoming golden- 

 buff during the summer. With the gaper {Anastomus 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 becoming white during the summer. :{ As an 

 instance of the second case, the young of the razor-bill {Alca torda, 

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

 ing the summer; and the young of the white-crowned sparrow of 

 North America (Fnngilla leu<^ophrys\ as soon as fledged, have elegant 

 white stripes on their heads, which are lost by the young and the old 

 during the winter. With respect to the third case, namely, that of 

 the young having an intermediate character between the summer 

 and winter adult plumages, Tarrell || insists that this occurs with 

 many waders. Lastly, in regard to the young differing greatly from 

 both sexes in tlieir adult summer and winter plumages, this occurs 

 with some hei 5ns 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 females in their summer 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 



*For illustrative cases see vol. iv, of Macgillivray's " Hist. Brit. Birds;" 

 on Tringa, etc., pp. 229, 271; on the Machetes, p. 172; on the Charadrim hiati- 

 cuia, p. 118; on the Charadtius pluviaiis, p. 94. 



t For the goldfinch of North America, FringtUa frisfis, Linn., see Audubon, 

 " Ornith. Biography," vol. i, p. 172. For the Maliu-i, Gould's *' Hand-book to 

 the Birds of Australia," vol. i, p. 318. 



1 1 am indebted to Mr. Blyth for information as to the Buphus; see also 

 Jerdon, " Birds of India," vol. iii, p. 749. On the Anastomus, see Blyth, in 

 " Ibis," 1867 p. 173. 



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

 FringUla lencophryg, Audubon, ibid, vol. ii, p. 89. I shall have hereafter to 

 refer to the young of certain herons and egi-ets being white. 



I History of British Birds," vol. 1, 1839, p. 159. 



