Febeuaky 23, 1900.] 



SCIENCE. 



295 



found in the embryonic condition, but these 

 may be readilj'^ accounted for in two ways, 

 for in no cases were fully changed feathers 

 so detected. (1) Where a partially changed 

 feather had been pulled out or shed and 

 was being renewed, and (2) where a feather 

 had begun to change before it was matured 

 (this being noticed in my parrot investiga- 

 tion). Many of the contradictory and con- 

 fusing remarks of dealers in birds may per- 

 haps be explained by these most important 

 observations, and it may readily be true 

 that more than a few instances of so-called 

 color changes depending upon spring moults 

 in cage birds, may be due to extensive 

 feather losses precedent to an Aptosochro- 

 matic change. 



It seems unnecessary to dwell upon the 

 fact that no vital process can readily take 

 place in a greatly injured organic structure, 

 and the renewal of my bird's feathers con- 

 current with the approach of the macro- 

 scopic activit3'^ of the color change is, I 

 think, an incident of no little value. 



The first appearances of a color change 

 were noticed in some of the old feathers 

 of the crown during the first week of 

 February. Here a brightening of the blue 

 area of the feather was noticed but no per- 

 ceptible change of color at the tips where 

 the russet was. From this date till the 

 death of the bird a slow but constant change 

 occurred, chiefly noticeable on the rump, 

 throat, and breast. The first indication of 

 the approach of the change externally was 

 the brightening of, the blue portion of the 

 feather, beginning evenly on each vane 

 from the bottom. When the band of tawny 

 was reached, it appeared slowly to be ab- 

 sorbed until but faint tips of this color 

 could be seen upon the ends of the larger 

 barbs. In no cases were the barbs or bar- 

 bules broken off sufficiently to account for 

 the change. A loss of one-third of the 

 length of the feathers in many cases would 

 have been the result, and close observation 



did not sustain this in the least. I was en- 

 abled to notice the change in certain breast 

 feathers, which was much more rapid than 

 that of the parrot before referred to. Yet 

 in the latter case the change which gradu- 

 ally causes the yellow plumage is a slow 

 one of life duration, and but few feathers 

 are involved at a time. That of Passerina 

 cyanea is one of comparatively short dura- 

 tion and involves the greater part of the 

 entire plumage. 



Upon his death the bird presented the 

 following appearance as regards color. An 

 irregular area of brilliant cobalt blue ex- 

 tended from the throat to the belly down 

 the center of the breast, the feathers upon 

 each side graduating gradually to the sides, 

 where but little change had occurred. Head 

 partially changed in parts, inter-scapulars 

 not perceptibly changed at all (a place 

 where many pin feathers formed). Back 

 altered slightly, rump and scapulars f 

 changed to bright greenish blue, the long 

 russet tips almost entirely changed in some 

 feathers, wings and tail unaltered with the 

 exception of the secondaries and coverts, 

 which had slightly changed on the edges. 

 Throat slightly blackish, lower ventral re- 

 gion as with the rump. Assuming, as we 

 safely may, that the first of February 

 marked the beginning of the macroscopic 

 change, we may attribute the total length 

 of time occupied in the change of some of 

 the breast feathers, from the fall to the 

 spring colors, to a period of about fifty 

 days, which for some of the feathers is an 

 over-estimate. 



It is not a little curious that the feathers 

 should act so independently and especially 

 so when it is considered that each feather 

 comes true in color. 



While skins of birds may serve highly 

 important purposes, it appears essential 

 that for good results in investigations upon 

 color change, one should operate rather upon 

 live birds in confinement. It is quite ab- 



