2 PASSERIFORMES. 



c 4 . Wing with true feathers and adapted 

 for powerful flight. 

 a 5 . External nostrils ordinary . . 8. Lariforjies. 

 b r >. External nostrils produced into 



tubes 9. Procellariiforsies. 



d*. Wing with no true feathers and 



fin-like 10. Spheniciformes. 



b. Young not born helpless and able at once, or 

 in a few hours, to avail themselves of the 

 instinct of self-preservation. 

 c 1 . Sternum with a keel. 



e". Palate desmognathous ; web-footed. 

 g 3 . Basipterygoid processes absent ; end 

 half of bill abruptly bent down- 

 wards 11. PHO3NIC0PTERIF0RMES 



h 3 . Basipterygoid processes articulate 

 with the pterygoids as near to the 

 palatines as possible ; end half of 

 bill never abruptly bent downwards. 12. Anseriformes. 

 f". Palate schizognathous. 



i 3 . Posterior processes of the ilium ap- 

 proximated to such an extent that 

 the sacrum is almost entirely con- 

 cealed. 



e 4 . Web-footed 13. Colymbiformes. 



/*. Toes lobed 14. Podicipedidiformes. 



k 3 . Posterior processes of the ilium never 

 approximated to such an extent 

 that the sacrum is almost entirely 

 concealed. 

 g*. Dorsal vertebrae heteroccelous. . 15. Galliformes. 

 h 1 . Dorsal vertebras opistoccelous . . 16. Charadriiformes. 

 cl 1 . Sternum with no keel 17. Struthioniformes. 



Order I. PASSERIFORMES. 



Young born helpless, and do not pass through a downy stage before 

 acquiring feathers. Palate segithognathous. Deep plantar tendons free ; 

 the flexor perforans digitorum serving the three front toes and the flexor 

 long us hallusis the hind toe. Ambiens and accessory femoro-caudal muscles 

 absent. Oil-glands present and nude. Spinal feather-tract well defined on 

 the neck. Dorsal vertebras heteroccelous. Only a left carotid artery. 



This Order comprises about three-fifths of the known species of birds, 

 and is represented in the Ethiopian Eegion by some 1500 of them. 



