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Clark, The Classification of Birds. lo t 



Anseriform. 



Upper cervical tract not separated from lower until near shoulder ; 

 forked, branches diverging somewhat. 



Dorsal tract directly continuous with upper cer\ical, thus enclosing a 

 more or less elongated apterium. 



Humeral tracts broad and strong, sometimes connected with the dorsal. 



Femoral tracts large, united with dorsal. 



Sternals directly continuous with lower ceryicals, and usually with a 

 prominent side-branch. 



Ventrals very broad, directly continuous with sternals ; ventral apter- 

 ium very narrow, and not notably broader behind. 



This Style characterizes the Petrels, Albatrosses, Pelicans and 

 other totipalmate birds. Auks, Geese, Ducks and vSwans. 



Falconiform. 



Upper cervical tract well-marked, usually narrow ; strongly forked 

 between the shoulders ; slightly or not at all connected with the dorsal 

 tract; branches diverging. 



Dorsal tract very variable, either broad or narrow, forked or solid. 



Humeral tracts strong but not very broad. 



Femoral tracts wanting or very weak ; the feathering of the tibia is 

 usually very full and a strongly marked patch sometimes crosses the 

 head of the tibia and runs along the femur a distance. 



Lower cervical tract considerabl% forked. 



Sternals very strongly marked. 



Ventrals narrow but widely separated on belly; ^yidel" on the breast and 

 more or less fused with the sternals; sometimes united only at the 

 furcula {Asia), sometimes also touching at edge of sternum {Sifix), and 

 sometimes united the full length of the breast {Pandion). 



This Style is shown by Vultures, Ha^vks, Owls, and other birds 

 of prey ; and probably Parrots also. 



Pelargiform. 



Upper cervical tract divided very deeply on the neck but the branches 

 not diverging. 



Dorsal tract solid or deeply forked (toward rear), moie or less connected 

 with cervical. 



Humeral tracts well marked. 



