230 DWIGHT 



than those of the ju venal plumage, and this points to their having 

 been completely renewed during the winter absence. 



5. Adult Winter Plumage acquired by a complete post- 

 nuptial moult. This dress is assumed after the birds have moved 

 southward in the autumn. 



6. Adult Nuptl^l PLU^L\GE acquired by wear. 



Fcuialc. — The sexes are indistinguishable in all plumages, and 

 the moults are probably identical. 



Stelgidopteryx serripennis (Aud.). Rough-winged Swallow 



1. Natal Down. No specimen seen. 



2. Juvenal Plumage acquired by a complete postnatal moult. 



Above, deep sepia-brown, edged with cinnamon-rufous. Wings and tail clove brown, 

 the coverts, secondaries and tertiaries edged with cinnamon-rufous. The outer 

 edge of the first primary is without booklets and therefore not rough to the 

 touch. Below, dull white, the breast and throat vinaceous cinnamon. Bill 

 and feet dusky flesh- color, becoming black. 



There is some fading and loss of feather edgings before the 

 birds leave us in the autumn. 



3. First Winter Plumage acquired by a complete post- 

 juvenal moult after the birds have migrated southward in Sep- 

 tember, or very likeh- while they mov^e leisurely along in flocks. 

 One young female (Am. Mus. Nat. Hist., No. 71520, October 

 24th, Key West, Florida), shows six new primaries partly grown 

 in each wing and a few new body feathers. Judging by spring 

 specimens taken in May the plumage when fresh must be deep 

 sepia-brown, darker on the pileum, with dusky shaft streaks 

 and slightly paler, indistinct edgings. Wings and tail darker 

 than in juvenal dress, males acquiring the saw-toothed outer 

 primary. Below dull white with a brownish mouse-gray pec- 

 toral band. 



4. First Nuptial Plumage acquired by wear which is much 

 more marked than in Swallows having iridescent plumage. 



5. Adult Winter Plumage acquired by a complete post- 

 nuptial moult after the birds have migrated southward. An 



