24 ALLEN'S NATURALIST'S LIBRARY. 



southwards in the autumn, while in some of the tropical coui 

 tries the species remain all the year round. 



I. THE COMMON CUCKOO. CUCULUS CANORUS. 



Cuculus canorus, Linn. Syst. 'Nat. i. p. 165 (1766); Macgil 

 Br. B. iii. p. 109 (1840) ; Newt. ed. Yarr. Brit. B. ii. 

 387 (1880); Dresser, B. Eur. v. p. 199, pi. 299 (1878) 

 B. O. U. List Br. B. p. 83 (1883) ; Seebohm, Br. B. ii. 

 378 (1884) ; Saunders, Man. p. 277 (1889) ; Shelley, Cat 

 B. Brit. Mus. xix. p. 245 (1891); Lilford, Col. Fig. Br. 

 pt. xviii. (1891). 



(Plate XXXIII.'] 



Adult Male. General colour above leaden-grey, with a slig 

 greenish gloss, the upper tail-coverts with white edges and bars 

 quills dark brown, with white notches on the inner webs ; tail 

 feathers slaty-black, with white ends ; on each side of the shai 

 twin spots of white, the inner webs notched with white, but nc 

 complete bars across the feathers ; sides of face and throat 

 rather lighter grey than the head ; remainder of under surface 

 of body white, regularly barred with black, with a tinge of buf 

 on the abdomen and under tail-coverts ; axillaries and under 

 wing-coverts barred with black ; bill black, light yellow at the 

 base of the lower mandible ; feet yellow ; iris yellow. Total 

 length, 14 inches ; culmen, 0*9 ; wing, 8-9 ; tail, 7'o ; tarsus, 0*8. 



Adult Female. Similar to the male, but a trifle smaller, and 

 distinguished by the rufous shade on the fore-neck. Total 

 length, 12-5 inches; wing, 8-3. 



"Young. Very different from the adults. Dark brown or 

 ashy-brown, barred with rufous, and with a white edging to 

 the feathers, producing a strongly mottled appearance ; on the 

 back of the neck a white spot ; under surface of body buffy- 

 white, barred with blackish-brown, more broadly on the throat ; 

 tail barred with rufous. 



There is also a rufous or "hepatic" phase of plumage in the 

 Cuckoo, which appears to be confined to the young birds only. 

 In this plumage the general aspect of the bird is tawny-rufous 

 or cinnamon, barred with blackish, the bars less distinct or 

 forming only spots on the rump and upper tail-coverts ; tail- 

 feathers rufous, tipped with white, before which is a sub- 





