ME. E. DEGEN ON ECDYSIS. 365 



not only in warmth of colour, but also in that lustre which imparts to them a finish 

 which makes them distinguishable even to the "touch alone" from the adult birds 

 (Altum (2), p. xxij. In a word, it is a provisional plumage. 



Its duration, according to the quotations of the different writers, seems to vary for 

 the families, the genera, and also for the different species amongst the latter; but on 

 this head, owing to observations being frequently based on unreliable material, there 

 is great confusion. 



According to Brehm (8) this first or fledgling-plumage is replaced in the genus Strix 

 by another of similar primitive quality — an observation which again called for a foot- 

 note from Dr. Cabanis (p. 344, I. c), in which he gives expression of genuine surprise 

 in the following manner : — " Also zivei DunenJcleicler ! " 1 &c., &c. " Bas ist in der 

 That selir hemerkensioerth" &c. But Brehm also showed that in the young of the 

 Owls the flight- and the tail-feathers, as well as the body-feathers, are shed in 

 the same season in which the bird was hatched, while in the Birds of Prey only 

 the body-feathers, excluding the remiges (and probably, too, the tectrices), are shed, 

 these latter being shed in their second autumn (Brehm (7), p. 196. & (8), p. 345). 

 This statement of Brehm was published only a year after the one in which Schlegel (40) 

 made the sweeping assertion that " the young birds moult for the first time in the 

 autumn of that year ivhich follo^vs the one in ivhich they were born"'^. As the 

 aforesaid statement formed one of the fundamental tenets of Schlegel's theory for 

 the alleged regeneration and revitalization of the bird's feathers, it should scarcely be 

 surprising to find that no sooner had it been published than it drew a host of 

 contradictions, not only from Brehm, but also from the ablest observers amongst 

 ornithologists of the time. Amongst the latter was Homeyer (30 a), who, after enume- 

 rating a considerable portion of the birds composing the list of genera and species claimed 

 by Schlegel for changing colour ivithout moult, irrevocably proved this colour-change 

 loith moult by emphasizing on p. 117 of the article, under the heading of " allgemeine 

 Grundziige," &c., on the first feather-change in the following conclusive words : — 

 " 6. AUe kleineren und viele grossere junge Vogel mausern voUstdndig im ersten 

 Herbste ihres Lehens." 



My own observation also disproves Schlegel's statement in regard to this wholesale 

 assertion. To the list, therefore, of birds which undergo their first total moult in the 

 season in which they are reared, I can add also Gymnorhina tibicen, the species which 

 has been under my particular consideration and upon which I base this paper. 



C. On " Perennial Feathering." 



The manner in which the feathers on the wing of a fledgling bird are replaced 

 in subsequent changes is strikingly different from that in which they acquired them at 



' The italics are mine. 



3f 2 



