27. ANAS. 



187 



27. ANAS. 



Type. 



Anas, Linn. S. N. i. p. 134 (1766) A. boscas. 



Anassus, Rqfin. Analyse, p. 72 (1815). 



Boschas, Siv. Fauna Bor.-Amer., Birds, p. 442 (1831) . . A. boscas. 



Range. Cosmopolitan. 



Key to the Species. 



a. Central tail-feathers curled up. 

 a'. No white ring round the eyes. 



a". Speculum purple-blue ; under tail- 

 coverts in full-plumaged males velvety 



black 



b". Speculum greenish blue ; under tail- 

 coverts (in full-plumaged males ?) 

 black, more or less mixed witli chest- 

 nut 



h', A ring of white feathers round the eyes. . 



b. Central tail-feathers not curled up. 



c'. Wing-speculum purple, green, or blue, 

 c". No transverse white bands across the 

 tail, 

 c'". Bill greenish olive or yellowish, but 

 not yellow with a distinct longi- 

 tudinal black patch on the culmen. 

 c'. Outer web of tertials not white. 



tc°. No very distinct black band 

 through the eyes, but sometimes 

 only an obsolete one. 

 c®. Throat and cheeks thickly 

 streaked with brown ; no 

 white band anteriorly to the 

 speculum. 

 c'. Speculum metallic green . . 

 (P. Speculum dark violet ; 

 general colour very dark . . 

 d'^. Throat usually not streaked 

 with brown; the light part 

 of the plumage more or less 

 rufescent. 

 e'. No white subapical band on 

 the last row of the upper 

 wing-coverts ; speculum 

 bluish green or greenish 

 blue. 

 e^. Secondaries with no white 

 band at the tip, or with 

 a very narrow one .... 

 /*. Secondaries with a very 

 distinct white band, 

 about 0'3o inch broad, 



at the tip 



y. A white subapical band on 

 the last row of the upper 



boscas, p. 189. 



icyvilliana, p. 196. 

 laysanensis, p. 199. 



melleri, p. 199. 

 ohscura, p. 200. 



fulvigula, p. 202. 

 maculosa, p. 203. 



aberti, p. 204. 



