262 DWIGHT 



Dendroica pensylvanica (Linn.). Chestnut-sided Warbler 



1. Natal Down. No specimen seen. 



2. Juvenal Plumage acquired by a complete postnatal moult. 



Above, dark raw umber-brown, obscurely streaked or spotted on the back with dull 

 black. Wings and tail dull black, chiefly edged with ashy or plumbeous gray ; 

 the secondaries, and teriiaries with olive-yellow, the coverts with buff forming 

 two wing bands yellow- tinged. Below, pale umber-brown, grayer on the throat 

 and sides of head, the abdomen and crissum dull white. Bill and feet dusky 

 pinkish buff, becoming black. 



3. First Winter Plumage acquired by a partial postjuvenal 

 moult, beginning late in June, which involves the body plumage 

 and wing coverts, but not the rest of the wings nor the tail. 



Unlike the previous plumage. Above, bright olive-yellow concealing black spots 

 on the back and rump, the upper tail coverts black, tipped with cinereous gray 

 and olive-yellow. The wing coverts black, edged with olive-yellow, two 

 broad wing bands canary-yellow mixed with white. Below, grayish white, 

 pearl-gray on sides of head, throat, breast and flanks, a trace of chestnut strip- 

 ing the flanks terminating in a lemon-yellow .spot. Conspicuous white orbital 

 ring. 



4. First Nuptial Plumage acquired by a partial prenuptial 

 moult which involves most of the body plumage and the wing 

 coverts, but not the rest of the wings nor the tail. Young and 

 old become practically indistinguishable, save for the browner 

 wings and tail of the young bird. The yellow crown, the black 

 and white about the head, the streaking of the back and the 

 lateral chestnut stripes of the throat and sides are acquired. 



5. Adult W^inter Plumage acquired by a complete postnup- 

 tial moult in July. Differs from first winter dress only in the 

 broad deep chestnut stripes on the sides, the greater amount of 

 black on the back and the slightly blacker win^s and tail, with 

 brighter edgings. 



6. Adult Nuptial Plumage acquired by a partial prenuptial 

 moult as in the young bird. 



Female. — The plumages and moults correspond to those of 

 the male, from which it is first distinguishable in first winter 

 plumage when the white below is duller the sides grayer and 

 the chestnut stripes altogether lacking. The first nuptial plum- 

 age, acquired by a limited moult, resembles that of the male in 



