THE COMMON BUZZARD. 143 



First summer. — Moult of juvenile plumage appears to take 

 place from April to Nov. In birds a year old before moult feathers 

 are often so worn that pale edgings on upper-parts do not appear 

 different from those in adults. After moult as adults. 



Measurements and structure. — ^wing 370-395 mm., tail 190-210, 

 tarsus 70-80, bill from cere 22-24 (12 measured). $ wing 380-410. 

 Primaries : 1st between 7th and 9th, 4th longest, 3rd equal or 

 5-15 mm. shorter, 5th rarely equal, usually 3-15 shorter, 6th 40-50 

 shorter, 2nd 30-50 shorter ; 2nd to 5th clearly emarginated outer 

 webs, 1st to 4th very abruptly emarginated and attenuated at tips 

 for about one-third of length. Outer secondaries shorter than 

 10th primary, inner ones becoming longer and longest equalling 

 8th primary, tips rather sharply rounded. Tail nearly square, 

 very slightly rounded laterally, 12 feathers, tips rounded. Half 

 (occasionally slightly less than half) tarsus feathered on front 

 only, toes short in comparison with Falco and claws not so much 

 curved. Bill much compressed, rather slender, upper mandible 

 curved with long slender point projecting beyond under mandible 

 which is short and blunt, no notches on cutting edges as in Falco. 

 Nostrils somewhat elliptical and sparsely covered by hair-like 

 tips of feathers of lores. 



Soft parts. — -Bill dark horn, paler at base ; cere, legs and feet 

 yellow ; iris dark brown to yellowish-brown. 



Characters and allied forms. — 'For differences of B. b. vulpinus 

 see under that form ; B. b. zimmermannce (north-west Russia 

 south to Balkans) has been separated as intermediate between 

 B. b. buteo and B. b. vulpinus but is doubtfully separable from 

 B. b. buteo ; B. b. arrigonii (Corsica, Sardinia) is like B. b. buteo 

 but rather smaller, with a slightly finer bill and under-parts are 

 striped and apparently never thickly barred ; B. b. insularum 

 (Canary Is.) is like B. b. buteo but with shorter wing and slightly 

 larger bill ; B. b. japonicus (Turkestan to Japan) is like B. b. buteo 

 but with more than half tarsus feathered ; B.b. harterti (Madeira), 

 B. b. rothschildi (Azores) and B. b. bannermani (Cape Verde Is.) 

 have also been described ; owing to great individual variation there 

 is considerable intergradation between various forms. Much 

 rounded wing, weak bill and feet, bristle-like feathers of lores and 

 half -feathered tarsus distinguish B. b. buteo from other British 

 " hawks." 



Field-characters. — No longer a common woodland species, but 

 now restricted to uncultivated hill-country and districts with 

 rocky coastline. At rest its size, robust build, dark brown upper- 

 parts and streaked yellowish-white under-parts are good characters, 

 unfeathered tarsi and lack of white in tail preventing confusion 

 with Rough-legged Buzzard. Flight in passing from place to place 

 slow and heavy, but its great wing-power appears to advantage 

 when bird soars, as it often does for hours at a stretch, and its 



