92 DWIGHT 



sprouted and precedes by a distinct interval feather loss in the 

 median coverts. They are usually renewed with the adjacent 

 body plumage, and are the coverts most likely to be renewed 

 if the wings show any moult at all. In some species there is a 

 striking difference in the color of these coverts by which young 

 birds one year old in breeding plumage may be distinguished 

 from those that are older, as for example in the Goldfinch 

 [Spiiiits tristis) or Red-winged Blackbird [Agelaius pJurnicciis.) 



Renewal among the under wing coverts which are often 

 spoken of as " lining of the wing" takes place after the moult of 

 the upper surface of the wing has been nearly or quite com- 

 pleted. They are among the last feathers to develop in young 

 birds after leaving the nest. The first row of those lying upon 

 the bases of the remiges remains as a rule until the adjacent 

 second row has been replaced. The moult begins among the 

 secondary coverts of the second row extending irregularly out- 

 ward and inward, the innermost being the latest, followed closely 

 by the second row of primary coverts. The first row completes 

 the moult of this surface of the alar tract, perhaps excepting 

 tlie tiny down feathers growing, at the bases of the secondaries 

 and over the wing membrane. 



The long infra-marginal coverts, a double row of alternating 

 long and short feathers that sweep backward over the compara- 

 tively bare under surface of the wing membrane, begin to fall 

 somewhat irregularly near the carpal joint, the row of long ones 

 preceding the short ones, and the moult moves inward, the 

 feathers close to the body being late in renewal. The thatch- 

 like row of lesser coverts that grow at the anterior margin of 

 the wing are equally late, the renewal being irregularly towards 

 the body from the carpal joint. 



The tiny carpo-nietacarpal coverts, or feathers of the wrist and 

 hand, both above and below may show moult early, but in 

 young birds the contrary prevails. The moult tends to pro- 

 ceed in the two principal median rows from the carpal joint, 

 distally. 



The few feathers of the iipper arm (excepting those of the 

 humeral tracts), especially those on its posterior edge, are 

 among the latest of the wing series. 



