1896.] NATURAL SCIENCES OF PHILADELPHIA. 117 



ing is complete, while in psilop?edic birds it is but very slightly- 

 developed. In prsecocial species the downy dress is retained for a 

 considerable time before the first feathers appear, but in altricial 

 birds it is soon replaced by what is known as the "first plumage." 

 The reraiges and rectrices of the first plumage are usually the same 

 as those of the adult, but the body feathers, while of the ordinary 

 structure, are much more pJumulaceous than the covering of the 

 adult. 



This first plumage is retained for some time (three or four 

 months) in some species, but in others it is very soon replaced by a 

 more permanent winter plumage in which all the feathers are of the 

 same structure as those of the adult. The entire body plumage is 

 molted at this time as5 well as most of the wing coverts ; but the 

 rectrices, remiges and the primary coverts are, in the great majority 

 of our smaller land birds, retained until the next annual molt. 



The species in which all the first plumage feathers are molted are 

 the following : Otocoris alpestris, Cardinalis cardinalis, Agelaius 

 phceniceus, Quiscalus q^dsciila, Molothrus ater, Sturnella magna, Scole- 

 cophagus carolinus, Tachycineta bicolor and all the Woodpeckers. 

 Of Ceryle, TrochUus, Chcetura and a few Oscines I have been unable 

 to examine sufficient specimens to speak with certainty on this point. 



In early spring, probably about the time of revival of sexual 

 activity and immediately preceding the vernal migration, there is in 

 the vast majority of birds a more or less complete molt. Some- 

 times, as in the case of the Bobolink, the change is absolutely com- 

 plete, but as a rule the remiges and rectrices are not renewed, 

 while in other species the molt may only amount to the acquisition 

 of a few new feathers on the throat or sides of the head. The 

 tertials are often renewed at this time and seem to correspond more 

 with the body feathers than with those of the wing as regards their 

 molting. It is at this season that many birds acquire marks of 

 maturity which are lacking during the first winter of their life, as for 

 instance, the yellow superciliary and loral stripes of certain finches, 

 while markings characteristic of the breeding season as opposed to 

 the winter, also appear at the time of spring molt. 



In studying the species of our smaller land birds which molt in 

 the spring it will be noticed that of necessity, species which difl^er 

 radically in their spring and fall plumage, have the most complete 

 spring molt ; while, as a rule, in those in which the plumage is nearly 

 the same throughout the year, the spring molt is least marked. The 



