294 



SCIENCE. 



[N. S. Vol. XI. No. 269. 



From February 11th to February 28th 

 an average of 50 contours was lost daily. 

 By March 5th the loss had abruptly ceased, 

 and until his death on March 29th the bird 

 lost but one or two feathers daily. The 

 loss of down feathers was very small, not 

 exceeding twenty specimens — a fact of pos- 

 sible importance to be dwelt upon later on. 

 The total summary of the contour feathers 

 lost, carefully estimated at 1350 feathers, 

 appeared to comprise about three-fifths 

 of my bird's entire plumage. They were 

 shed from all parts of the plumage, and in 

 view of the heavy loss I was quite prepared 

 to ultimately conclude that any color 

 change resulting in my bird would ensue 

 from extensive feather loss. I was thus 

 quite unprepared for what eventually fol- 

 lowed. Microscopically, the cast-off feath- 

 ers were broken, abraded and apparently 

 in the worst condition. The barbules were 

 broken or wanting, the barbs in many 

 places worn down, and the rhachis of the 

 larger feathers was split. This is also of 

 importance as will directly be seen. To 

 many observers my bird by March 5th 

 would have been pronounced to be com- 

 pletely moulting. Immature feathers were 

 in prominence especially upon the head and 

 were scattered all about the remaining 

 feathers of the plumage, which, as has been 

 before remarked, amounted to about two- 

 fifths of the entire plumage. The color of 

 a discarded feather, compared with a freshly 

 plucked one from the body, showed in most 

 cases a decided contrast. N'ot only were 

 the blue portions dull but their superstruc- 

 tures were gone in many cases, the feathers 

 then being dull brownish. A probable, and, 

 as I am convinced, the truthful source of 

 my bird's extensive loss is found indirectly 

 in the temperament of the bird. From the 

 very first it was fretful and timid, flutter- 

 ing wildly when uncovered in the morning 

 or when the cage was cleaned out. Even an 

 approach in his direction while hanging in 



the room caused a wild fluttering. Upon 

 such occasions many feathers would be 

 shed, and those remaining were more or less 

 injured. Thus when such a vital process 

 as Aptosochromatism begins to work, these 

 decrepit feathers necessarily would have to 

 be renewed in order to take part in the 

 general plan. The head upon which many 

 pin feathers appeared, naturally received a 

 considerable share of the injury as regards 

 its feathers, and the tail was in a vei-y bad 

 state. 



It will be noticed in the table how gradu- 

 ally the loss began, due doubtless to the 

 gradual approach of activity towards color 

 change in the feathers. It must be ad- 

 mitted that this explanation is purely hy- 

 pothetical, but such a hypothesis, although 

 not of fundamental importance, ofttimes 

 prepares the way for a clearer understand- 

 ing of the problem under consideration. 

 The small loss of down feathers points in 

 two ways to the truth of this assumption. 

 Firstlj', being more or less under the con- 

 tour feathers they received less of the wear 

 caused to the others, and secondly, having 

 no color change in themselves, their part in 

 the color-changing process was inconspicu- 

 ous. It is not probable that the bird could 

 have swallowed many down feathers with- 

 out it being observed in the excrement. 



As I frequently examined the bird closely 

 I noticed at once that the developing feath- 

 ers which were supplying the places of the 

 cast-ofi" ones, far from appearing to change 

 the color of the bird to blue, were actually 

 coming true to the colors in which they 

 were shed, i. e., in the colors of the fall 

 plumage. To be positive I collected and 

 examined extensively and in every case 

 verified this most interesting principle. It 

 will be recollected that in my observations 

 upon the Aptosochromatism of Chrysotis 

 Levaillanti (see Osprey, III., No. 8, April, 

 '99), similar results were noticed. In later 

 dates a few parti-changed feathers were 



