166 PROCEEDINGS OF THE ACADEMY OF [1896. 



EXPLANATION OF PLATES. 



Plate IV. 



Fig. 1. Wing of Merula migratoria with molt started ; shaded parts 

 represent the new feathers. Quill No. 6 has been shed but 

 the new feather has not yet appeared. 



Fig. 2. Wing of Tachycineta bicolor ; molt of primaries well ad- 

 vanced. 



Fig. 3. Wing of Chcetura pelagica, with molt of primaries well ad- 

 vanced. 



Fig. 4. Tail of Tachycineta bicolor, with molt of rectrices half com- 

 pleted. 



Fig. 5. Breast feather of Antrostomus vocifertis, first plumage, bear- 

 ing a down feather at its tip (much enlarged). 



Fig. 6. Tip of breast feather in sheath of Sturnella magna, winter 

 plumage ; forcing out a first plumage feather on its tip (en- 

 larged). 



Fig. 7. Feather from breast of DoUchonyx oryzivorus Ad. $ show- 

 ing light border which is lost by abrasion. 



Fig. 8. Terminal part of tertial of Sturnella magna, winter plumage. 



Fig. 9. Same in late summer, showing loss of entire terminal por- 

 tion even with the tips of the secondaries ; also loss by 

 abrasion of all the light border and spots, including the 

 entire terminal part of the barbs, from where the light color 

 beo^ins to their extremities. 



■^o 



Plate V. 



Fig. 1. Tail of Dryobates pubescens showing the beginning of the 



molt. The third quill has just been shed and the tip of the 



new one has not yet appeared. 

 Fig. 2. Tail of Galeoscoptes carolinensis showing the molt under way. 

 Fig. 3. Wing of Ceryle alcyon showing the beginning of the molt 



with the fourth primary, instead of the innermost as is 



usually the case. 

 Fig. 4. Wing o^ Plectrophenax nivalis with molt of primaries and 



tertials in progress. 

 Fig. 5. AVing of Dendroica cestiva showing molt of primaries and 



tertials almost complete, while the secondaries are about 



half grown. Dotted line represents the position of feathers 



when the growth is completed. 



