142 



ANATID^. 



Subfamily VII. ANATIN^. 



Dendroctcna, 



[p. 144. 



Key to fJie Genera. 



Lower portion of tarsus in front without 

 transverse scutellfB, but covered with 



small rt?ticulate scales 23, 



Lower portion of tarsus in front with a row 



of transverse scutellte. 



b\ Wing-speculum more or less conspicuous, 



but always present. 



b" . Outer web of tertials chestnut ; upper 



wing-coverts white, except in Chennlo- 



pex jubatus, which has them black ; 



size rather large. 



P. Edges of the bill with no prominent 



lamellfe 24. Chenalopex, 



e^. Edges of the bill with more or less [p. 166. 



prominent lamellae, 

 c*. Bill broader towards the tip than 

 at the base ; culmen rather con- 

 cave ; lamellfe more developed 

 towards the tip of the upper man- 

 dible ; lower mandible with the 

 lamellfe not projecting outwardly ; 



feet flesh-colour : sexes similar . . 25. Tadorna, p. 170. 

 d^. Bill not broader towards the tip 

 than at the base ; culmen almost 

 straight ; lamellfe equally deve- 

 loped along the inner edge of the 

 upper mandible ; lamellfe on the 

 edge of the lower mandible pro- 

 jecting outwardly ; bill and feet 



dark : sexes dissimilar 26. Casaeca, p. 177. 



c". Outer web of tertials not chestnut ; 

 tail-feathers not broad and not rounded 

 at the tip, but usually more or less 

 pointed; colouring of the plumage 

 more or less mottled, not in large 

 uniform patches, except on the ■sving- 

 coverts. 

 dP. Bill not spatulate. 



e^. Upper wing-coverts not blue, but 

 of a more or less dark grey. 

 e". Tail moderate, -R^th the central 

 tail-feathers not very long. 

 e'^. BiU broad, about the length of 



the head 27. Anas, p. 187. 



/". Bill not very broad, more or 



less compressed, and shorter 



than the head. 



f. Speculum generally with 



metallic gloss, sometimes 



black, or black and white. 



