32 
HINTS ON CAGE-BIRDS. 
Pekin Nightingales, and these birds we it: being sold in the London 
bird shops at very low prices. I bought three dozen, and selected 
what I supposed were sexes (judging them by colour of throat and 
4 c ■ 
Sexual Differences in Heals of Robins. 
wing alone) ; not one of these birds ever came into song, nor did 
any of them ever lose the black stain at the base of the bill. 
Where there are no marked colour differences in the plumage of 
the sexes of Parrots, you should examine the cere and the iris, and 
see whether these do not show sexual distinctions. If you fail in 
this, examine the outline ofjhe bare patch on the face (common in 
many Parrots), whether rounded or somewhat pointed at the back ; 
feel the hinder angle of the lower jaw, and see whether there is not 
a marked difference in the pointed or rounded character of that 
angle; note whether the crown is short and arched, or long and 
flatfish ; and, lastly, whether there is not a noticeable discrepancy 
in the length of the wing. Some of these characters are sure to 
help yon unless your appreciation of differences is defective, 
in which case you may possibly be successful if you select the 
largest and smallest birds from a batch. 
Of the sexing of uniformly coloured Doves little is known, 
therefore large and small examples are generally put together 
as pairs, often with happy results. I, however, Borne years since, 
lost the hen of a pair of Bar-shouldered Doves, and replaced it by 
a bird smaller than my male, which was confidently regarded as a 
Sexual differences in Bills and Head of Pekin Nightingale. 
