ACCIPITRES. 191 



Suborder XVI. ACCIPITRES. 



Young born helpless^ but completely covered with down ; no basi- 

 pterygoid processes ; spinal feather-tract well defined on the neck ; 

 hallux present, and connected with the flexor longus hallucis, and not 

 with the flexor perforans digitorum, the two tendons bound together 

 by a fibrous vinculum ; dorsal vertebrae heterocoelous. 



The Birds of Prey may be regarded as cosmopolitan in their 

 distribution. They number about 350 species, of which 20 have 

 occurred in the Japanese Empire. 



The Japanese genera of Accipitres may be divided into three 

 groups founded upon the peculiarities of the covering of their tarsi ; 

 but until the osteology of the Birds of Prey has been examined, it 

 is impossible to say how far these groups are natural ones. 



Falconing. — Lower half of tarsus reticulated all round. 



Bill deeply notched Falco ...... ^j^.^^ ^^5,^^^^ ^^^^^^^ ^^^ ^^^^^ 



\ and fifth. 

 Pandioii . . J 



But aster. 



Lores covered with small feathers, I „ 



, . ' > Perms. 

 not hairs 1 



Aquilin^e. — Tarsus scutellated or feathered in front ; reticulated 

 or feathered at sides and back. 



CMilvus. "^ 



m, . J „ ., J/..-!, . • }• Tarsus scutellated in front. 



Ihird, fourth, and nfth primaries J jt y f I 



longest ] " "] 



, , , . . i--^?'«'«- Uail not forked. 



Tarsus feathered m front to the J | 



toes [ Spizaetus. J 



AcciPiTRiN^.— Tarsus scutellated at back and almost always in 

 front ; reticulated at sides. 



Buteo. j Tarsus less than a fourth of wing, 



\ and less than half of first pri- 

 Carpal joint to tip of shortest 1 Circus. { maxy. 



primary much less than length \ 

 of tail ( Accipiter. 



