24 
Allen’s naturalist’s library. 
southwards in the autumn, while in some of the tropical coun- 
tries the species remain all the year round. 
I. THE COMMON CUCKOO. CUCULUS CANORUS. 
Cuculus canorus, Linn. Syst. Nat. i. p. 165 (1766); Macgill- 
Br. B. iii. p. 109 (1840); Newt. ed. Yarr. L'rit. B. ii. p- 
387 (1880); Dresser, B. Eur. v. p. 199, pi. 299 (1878); 
B. O. U. List Br. B. p. 83 (1883) ; Seebohm, Br. B. ii. p- 
378 (1884) ; Saunders, Man. p. 277 (1889) ; Shelley, Cat- 
B. Brit. Mus. xix. p. 245 (1891); Lilford, Col. Eig. Br. B- 
pt. xviii. (1891). 
{Plate XXXiri.) 
Adult Male. — General colour above leaden-grey, with a slight 
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 shaft 
twin spots of white, the inner webs notched with white, but nO 
c-omplcte 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 buff 
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, S'p ; tail, yo; tarsus, o'S- 
Adult Female. — Similar to the male, but a trifle smaller, and 
distinguished by the rufous shade on the fore-neck. Total 
length, i2'5 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 th® 
back of the neck a white spot; under surface of body buffy' 
white, barred with blackisli-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 of 
forming only spots on the rump and upper tail-coverts ; tail' 
feathers rufous, tipped with white, before which is a sub' 
