THE YOUNG LIKE BOTH ADULTS. 
209 
j| Up, 
XVI. 
JJVtfted through sexual selection by the nearly mature 
j es ’> but that, differently from what occurs in the 
gt 0 dust classes, the transmission, though limited to the 
ie age, has not been limited to the same sex. Conse- 
both sexes when mature resemble each other 
^ differ from the young. 
/o J ’ AS ‘ S ^' |T- When the adult male resembles the adult 
~ ni ale, tj ie young of both sexes in their first plumage 
Se >atZe the adults. — In this class the young and the 
Cob 8 ^oth sexes » whether brilliantly or obscurely 
°Ured, resemble each other. Such cases are, I think, 
j 0,6 common than those in the last class. We have 
* England instances in the kingfisher, some wood- 
<‘ol erS ’ ^ le j»y* raa gP' e , crow, and many small dull- 
^ cured birds, such as the hedge-warbler or kitty-wren. 
t j' !t the similarity in plumage between the young and 
. 0 old is never absolutely complete, and graduates away 
o 0 dissimilarity. Thus the young of some members of 
kingfisher family are not only less vividly coloured 
s ai1 the adults, but many of the feathers on the lower 
4 ,, aee are edged with brown, 27 — a vestige probably of 
° l 'Uier state of the plumage. Frequently in the same 
j^ 0,1 P of birds, even within the same genus, for instance 
V( atl Australian genus of parrokeets (Platycercus), the 
y 1,1,1 g of some species closely resemble, whilst the 
of other species differ considerably from their 
a le uts of both sexes, which are alike . 28 Both sexes 
Ct - l ' le youu S’ ot " the common jay are closely similar ; 
(jj 111 the Canada jay ( Perisoreus canadensis ) the young 
(| s o much from their parents that they were formerly 
S| ' l 'ibed as distinct species . 29 
9f thf J ^ lo . n ’ ‘ Birds of India,' vol. i. p. 222, 228. Gould’s ‘Handbook 
’°uld, Ibid. vol. ii. p. 37, *1G, 56. 
Sa 1 thirds of Australia,’ vol. i. 124, 130. 
ss ,'° U W, Ibid. vol. ii. p. 37, -16, 56. 
Audubon, ‘ Ornith. Biography,’ vol. ii. p. 55. 
v Or ~ 
II. 
