B. CLASSIFICATION 
ACCORDING TO STRUCTURAL 
PECULIARITIES 
I. Bill. 
II. Crest. 
III. Legs. 
IV. Tail. 
V. Sexual Dimorphism. 
I. BILLS 
Birds with Long Bills 
1. The Sunbirds (106-108). (Very small 
birds with long curved bills.) 
2. The Kingfishers (118-120). (Fairly long 
and straight.) 
3. The Hornbills (121 and 122). (Big birds 
with long tails.) 
4. The Hoopoe (123). (Bill very long and 
slightly curved.) 
5. The Black-winged Stilt (187). (Fairly 
long, very slender.) 
6. The Avocet (188). (Fairly long, slender, 
with an upward curve.) 
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