Chap. XYI. 
CLASSES OP CASES. 
187 
KULES OR CLASSES OF CASES. 
I. When the adult male is more beautiful or con- 
: spicuous than the adult female, the young of both sexes 
in their first plumage closely resemble the adult female, 
as with the common fowl and peacock ; or, as occasion- 
, ally occurs, they resemble her much more closely than 
they do the adult male. 
II. When the adult female is more conspicuous than 
the adult male, as sometimes though rarely occurs, the 
young of both sexes in their first plumage resemble 
the adult male. 
III. When the adult male resembles the adult female, 
the young of both sexes have a peculiar first plumage 
of their own, as with the robin. 
ly. When the adult male resembles the adult female, 
the young of both sexes in their first plumage resemble 
the adults, as with the kingfisher, many parrots, crows, 
hedge-warblers. 
V. When the adults of both sexes have a distinct 
winter and summer plumage, whether or not the male 
differs from the female, the young resemble the adults 
of both sexes in their winter dress, or much more rarely 
in their summer dress, or they resemble the females 
alone ; or the young may have an intermediate cha- 
racter ; or again they may differ greatly from the adults 
in both their seasonal plumages. 
VI. In some few cases the young in their first plumage 
differ from each other according to sex; the young 
males resembling more or less closely the adult males, 
and the young females more or less closely the adult 
females. 
Class I. — In this class, the young of both sexes 
resemble, more or less closely^ the adult female, whilst 
the adult male differs, often in the most conspicuous 
