238 DWIGHT 



5. Adult Winter Plumage acquired by a complete post- 

 nuptial moult. Practically indistinguishable from first winter, 

 but with less buff in some cases. 



6. Adult Nuptial Plumage acquired by wear, as in the 

 young bird. 



Female. — The sexes are alike and the moults are identical. 



Vireo flavifrons Vicill. Yellow-throated Vireo 



1. Natal Down. Drab. 



2. Juvenal Plumage acquired by a complete postnatal moult. 



Above, smoke-gray. Wings and tail black, edged with olive-gray, the secondaries 

 and tertiaries with olive-green (the two inner tertiaries white edged), the 

 greater and median coverts with dull white forming two wing bands. Below, 

 silky white, the chin, throat and sides of head pale canary-yellow, the orbital 

 ring, ocular region and superciliary stripe still paler. Bill and feet pinkish buff 

 becoming dusky and slale-gray when older. Iris deep hazel-brown. 



3. First Winter Plumage acquired by a partial postjuve- 

 nal moult in August, which involves the body plumage and the 

 wing coverts but not the rest of the wings nor the tail, young 

 and old becoming practically indistinguishable. 



Similar to previous plumage but greener above. Above, including auriculars and 

 sides of neck, bright olive-green, scapularies and rump, olive-gray. The lesser 

 wing coverts are edged with dull olive-green, the median and greater with 

 pure white, fonning two broad wing bands. Below, bright canary-yellow ex- 

 tending to orbital region and superciliary stripe ; abdomen and crissum white, 

 the flanks faintly washed with olive-gray. 



4. First Nuptial Plumage acquired by wear, the olive 

 above fading a little, the yellow below hardly at all. 



5. Adult Winter Plumage acquired by a complete post- 

 nuptial moult, and practically indistinguishable from first winter 

 dress, the wing edgings, especially of the lesser coverts and of 

 the scapularies grayer. 



6. Adult Nuptial Plumage acquired by wear as in the 

 young bird. 



Female. — The sexes and moults are alike. 



