t()2 FALCO PEREGRINUS. 



"Falcon" (female), ''Tiercel" (male), in Falconry; "Duck-Hawk" in America. 



Bhyri (female), Bhyri haclia (male), Hind. ; Bhyri Vega, Tel. ; Dega, Yerklees (apud Jerdon) ; 



Bahri or Water-haunting Bird, Turkestan (apud Scully) ; Basi, Persia (apud Pallas) ; 



Raja wali, Malay ; Sikap lang, Sumatra (apud Raffles) ; Laki Angin of the Passmu- 



mahs ; Halcon, Spain. 

 Ukussa, Sinhalese. 



Adult male. Length to front of cere 15'2 to 16-0 inches : culmen from cere OS ; wing 12-6 to 12-8; tail 6"5 ; tarsus 

 1-9 to 2-05 : middle toe 1'85 to 1'9, claw (straight) 0-65 to 07. 



Adult female. Length to front of cere 17 - 5 to 18-5 inches ; culmen from cere P05 to 1'2; wing 14-0 to 14-6 ; tail 

 7-3 to 8-5 ; tarsus 2-1 to 2-2 ; middle toe 2-1 to 2-3, claw (straight) 0-75 ; height of bill at cere 0-45 to 0-48. 

 Weight of a female (wing 14-5) killed at Trincomalie 2 lb. 4 oz. 



Iris dark hazel-brown; eyelid and cere above nostril rich yellow, greenish near the gape ; bill pale blue at the cere and 

 yellowish at the base beneath, darkening to blackish at the tips ; legs and feet yellow. 



\bove bluish ashen, darkening into blackish or blackish brown on the head and hind neck, and paling into bluish grey 

 on the rump and upper tail-coverts, all the feathers with dark shafts conspicuous on the back and scapulars, and 

 banded with narrow, softened, wavy bars of cinereous blackish from the hind neck downwards : on the rump and 

 upper tail-coverts these markings take a spear-shaped form; bases and sides of the feathers, in many examples, 

 on the hind neck rufescent : least wing-coverts edged pale ; quills dark brown, pervaded with ashy on the outer 

 webs ; the tips finely edged with greyish, the inner webs barred with rufescent grey or greyish white ; tail dusky 

 ashen, palest at the base, and crossed with narrow wavy bauds of blackish, and tipped deeply with buff-white. 



Forehead usually whitish close to the cere; lores, cheeks, and a short broad moustachial streak black ; chin, throat, 

 fore neck, and all beneath with the under wing-coverts white, tinged on the upper breast with faint isabelline grey, 

 and often on the lower parts with bluish grey ; the throat and fore neck unmarked, the chest streaked with narrow 

 shaft-stripes of brown, which change gradually on the upper breast into the narrow wavy bars of blackish brown 

 of the whole under surface and thighs ; under wing-coverts with broader bars of the same. 



06s. It is the opinion of many naturalists, and among them Mr. J. Hancock, who has made the Falcons a life-long 

 study, that the Peregrine, as well as other members of the genus, acquires its adult plumage at the first moult*. 

 From observations I have made of a number of specimens in the barred plumage, but showing here and there a 

 thorough immature feat her, it seems evident to me that the change does take place in the second year. Notwithstand- 

 ing this, however, it is equally evident that modifications take place in the adult plumage as the bird grows older ; the 

 streaks on the chest become finer and less numerous, and the change to the bars just beneath is more sudden than 

 in the two-year old. Considerable variety exists in the depth of hue of the upper surface in birds from different 

 parts of the world, and some examples are very rufous beneath ; an instance of this coloration is afforded in the 

 bird now in the Zoological Gardens, captured off Yucatan, which is almost as rufous as the Indian Peregrine. 

 Asiatic-bred birds shot in India seem to be, as a rule, very heavily streaked on the chest. 



" Young mule, on leaving the next (Sharpe, Cat. B. i. p. 378). Brown, all the feathers edged with rufous, a clear 

 greyish shade pervading the upper surface, and particularly distinct on the secondaries ; head and neck rusty buff, 

 i lie Miles of the crown and occiput, the nape and hind neck, the feathers behind the eye, and the moustachial line 

 mottled with blackish ; under surface of the body rusty buff, with longitudinal median spots of dark brown, fewer 

 on the thighs, and changing into bars on the under wing- and tail-coverts ; throat paler and unspotted."' 



The bird of the year attains almost its full size before the first moult, and has the cere and bill much as in the adult ; 

 legs and feet greenish yellow. 



When fully acquired the plumage is as follows : — Head, back, and wings dark brown, paling, in some, on the rump 

 into light umber-brown, in others into cinereous brown, the feathers more or less edged with rufescent brown, 



s Mr. Hancock argues from the testimony of caged specimens in bis possession, which have invariably acquired the 

 barred plumage at the first moult. Now all who have kept Raptors in confinement know that they are slower in acquiring 

 their adult plumage, owing to loss of vigour, than when in a wild state ; if, therefore, the Peregrine makes the sudden 

 change in captivity, how much more must it do so in a state of nature. 



