88 How to Sex Cage Birds. 



whether this is a sexual distinction or due to age does not appear. 

 As we know that the English Jay when young has blue irides but 

 afterwards they become vinous-brownish, it seems probable that the 

 birds with white irides may be immature. 



Carrion Crow (Corvus corone). 



Judging from an examination of the Museum skins, the bill of 

 the male in this species is remarkable for being slightly heavier and 

 shorter than that of the female. The plumage is a trifle more glossy, 

 but does not seem to differ in other res]jects. 



Hooded Crow (Corvus comix). 



The female is slightly smaller than the male ; the bill a trifle 

 longer, as in C. corone, but with heavier lower mandible, and 

 broader throughout when viewed from above ; the mantle and back 

 are rather browner (less ashy) than in the male. 



WlIITE-NECKED CkOW (CoVViix sc<i /mlal lis). 



The sexes are much alike, but the female is perhaps a trifle 

 smaller and duller in colouring, with shorter but heavier bill. 



Rook (Corvus frugihgus). 



The female is slightly smaller and less glossy than the male. 



We now come to the Crow-Shrikes, Piping-Crows, and Butcher- 

 Crows, which have been placed near the Shrikes, hut which the 

 Zoological Society of London still regards as aberrant Corvidce. 



As with the latter birds, the female usually has the shorter ami 

 stouter hill. 



Crow-Shrikes (Strepera). 



Pied Chow-Shrike (Strepera graculina). 



Sexes remarkably similar in plumage, hut the female is always a 

 trifle smaller than the male. The same remark applies to the Sooty 

 Crow-Shrike (,S r fulu/inosa) ; but, according to Gould, no such 

 difference exists between the sexes of the Hill Crow -Shrike (S. arguta) 

 and the Grey Crow-Shrike (S. anaphonensis), which he says can 

 only be sexed by dissection. He probably never compared the out- 

 line of the bills of male and female, or failed to recognise its 

 importance. 



Piping Crows (Gymnorkma). 



White-backed Piping-Crow (Gymnorhina leuconota). 



The female of this species has a shorter and stouter bill than the 

 male; the nape, back, and rump ash-grey; the back and rump with 

 blackish shaft-streaks and mottled white tips to the feathers. I 

 take this description from an old female sent to me in the flesh, and 

 it nearly approaches other examples in the Museum collection which 



