228 MOTACILLA YARRELLI. 



Female. — The female is similar to the male, but somewhat 

 less. The colouring is the same, but the crescent on the lower 

 part of the fore-neck is not so large ; there is more grey on the 

 back, and the edgings and tips of the wing-coverts are greyish- 

 white. Young females have the back all grey. 



Length 7| inches ; extent of wings 11^. 



Male in Summer. — In spring a change is produced in the 

 colouring by the addition of a patch of black feathers to the 

 throat, filling up the space between the crescent and the bill ; 

 and as the season advances the extent of dusky grey on the 

 back is diminished, not by the obliteration of the tips of the 

 filaments, but by the substitution of black for grey feathers. 

 In summer the male is as follows. The bill and feet are deep 

 black. The forehead, cheeks, supraocular space, and a broad 

 band passing down each side of the neck, are pure white ; 

 as are the breast, abdomen, lower tail-coverts, the two lateral 

 tail-feathers on each side, except a band along their inner 

 edges, the tips of the first row of small coverts, the edges 

 and tips of the secondary coverts, and the outer edges of the 

 three inner elongated secondaries ; the sides however are tinged 

 with grey. The fore-neck, lower part of the sides of the neck, 

 the hind part of the head and neck, and the anterior half of the 

 back are deep glossy bluish-black ; the rump and upper tail- 

 coverts similar, but a portion of the back still tinged with grey. 

 Smaller wing-coverts brownish-black, edged with grey. Quills 

 and tail-feathers, as in winter, but with the edges and tips 

 worn. 



Length of an individual in this state 7^ inches ; extent of 

 wings 12 ; tarsus {^ ; middle toe and claw i%- 



Female in Summer. — The female is similar to the male ; but 

 with more grey on the back, the black on the fore-neck tinged 

 with grey ; the lower parts greyish-white ; the two middle 

 feathers of the tail brownish-black. 



Length to end of tail 7i inches ; extent of wings lOf. 



Variations. — The principal variations that I have observed 



