14 INDIAN DUCKS 



Key to the Species. 



A. Lores and triangular patch between forehead and gape 



yellow or orange-yellow, never black. No knob at base 

 of bill. 



a. Yellow on bill extending right up to the nostril and 



sometimes still further towards tip of bill cygmis. 



b. Yellow never reaching to nostril and generally confined 



to somewhat circular patch on base. 



a . Bill longer, broader but less high at the base in com- 

 parison. Sen-ations hardly visible on bill when 

 closed minor. 



h' . Bill shorter, not so broad but comparatively high at 

 base. Serrations visible along nearly whole length 

 of bill when closed hetvicki. 



B. Lores and triangular patch black. A knob at base of l.)ill 



in adults olor. 



