COLOUE-CHANGES WITHOUT MOULTING 157 



feathers. The last to be affected by this change of colour are the 

 upper and lower tail-coverts, in which, indeed, it appears sometimes 

 to remain altogether in abeyance. 



In the Bar-tailed Godwit, and undoubtedly also the Black-tailed 

 Godwit, the changes in colour from the winter to the breeding 

 plumage proceed in a similar manner : in the case of the latter 

 species, the material for observation at my command is however 

 limited. 



A phenomenon of the highest interest, and one closely connected 

 with the changes of colour, is the restoration of the worn portions 

 of the feathers in regard to which so much doubt has been 

 expressed ; this, as has already been mentioned several times, 

 especially affects the edges of the feathers, which in the case of 

 many birds of the Snipe family have, as it were, become jagged 

 or serrated by wear. Much instructive material in regard to this 

 process is furnished by the various species of Totanus occurring 

 on this island. Unfortunately I was not able to extend my obser- 

 vations to Curlews as much as I should have liked, since these birds 

 are but rarely killed here in the spring. 



Although, in the case of the different species of Totanus, the 

 change of colour from the winter to the breeding plumage likewise 

 presents us with many surprising phenomena in regard to the 

 restoration of worn portions of the feathers, only three species, viz. 

 the Spotted Redshank, the Marsh and Wood Sandpiper, are of 

 special importance, in all of which the margins of the posterior 

 flight-feathers and the larger feathers of the upper parts also show 

 light triangular spots. These light spots, however, are so little able 

 to stand wear, that by the end of the winter they have almost or 

 entirely disappeared, as a result of which the remaining portions of 

 the feathers have acquired jagged edges something like the cutting 

 edge of a saw. It is this edge which, in the course of the colour 

 changes, is completely restored. The most comprehensive material 

 for the determination of this process has been supplied to me by the 

 Wood Sandpiper. The winter plumage of this bird is dull olivaceous 

 brown on the upper parts, and marked with small light spots at the 

 sides of the feathers, the markings not displaying a sharp contrast 

 with the ground colour. These spots increase in number and size 

 with the increase in size of the feathers, and at the same time gradu- 

 ally assume a triangular form, being disposed in close rows at the 

 edges of the long posterior flight-feathers. As we have said above, 

 the light portions of the feathers are so little capable of resisting 

 wear, that they entirely disappear in the course of the winter, the 

 edge of each feather being thereby formed into a zigzag line. 



The alteration of colour of this worn plumage to the fresh, gaily 



