158 THE BIRDS OF HELIGOLAND 



coloured breeding garb commences by the shafts of the feathers of 

 the upper parts becoming blackish at the tips, whence this colour 

 spreads on both sides over the whole lower half of the feathers, while 

 the light spots at their sides assume a more decided whitish tint. 

 At the same time the serrated indentations of the worn posterior 

 flight-feathers, scapulars, and greater wing-coverts, are restored to 

 completeness, the abraded tips of the barbs which formed the light 

 lateral markings being restored this time to a nearly pure white 

 colour. This process does not extend simultaneously to all the 

 posterior flight-feathers, but these latter present all kinds of transi- 

 tional stages in the course of their transformation. When this is 

 complete, the feathers are of a dusky black colour, the large trian- 

 gular spots at their margins nearly white, the serrated indentations 

 of the edges of the feathers are filled out, and the whole plumage 

 has the appearance as if it had just been renewed by moulting. 



In the Green Sandpiper, the change of colour to the summer 

 plumage proceeds exactly as in Glareola, but is less striking, inas- 

 much as in this species the ground colour of the feathers of the 

 upper parts in the summer plumage is less dark, and the marginal 

 spots less light and large than in the Wood Sandpiper. 



In regard to the Spotted Redshank, I have, I am sorry to say, 

 only limited material at my command ; still, such as I have, affords 

 me sufficient proof that, in this case also, the alteration of colour is 

 accompanied by a similar regeneration of the white triangular 

 marginal spots of the posterior flight-feathers and greater wing- 

 coverts, these markings being much larger in this species than in 

 the others previously considered. 



The Greenshank on its arrival here in spring is no longer in 

 perfect winter plumage, the alteration of colour having indeed 

 almost passed through its first stage, for the whitish ground 

 colour of the plumage of the upper parts of the winter plumage 

 has already yielded to a rich silver grey, though the feathers still 

 bear the numerous dark-bluish grey marginal spots. The subse- 

 quent course of the transformation may however be followed in an 

 extremely clear manner in individuals which one meets with here 

 in May. In them the shafts of the feathers first become deep black 

 along their whole length, the colour soon spreading as a beautiful 

 pure velvety black over both webs of the feathers of the upper 

 plumage, only leaving two broad margins, which simultaneously 

 acquire a white colour and lose their small dark spots. The change 

 proceeds most rapidly in the large scapulars, but, strange to say, in 

 the feathers of the back it only extends to the outer webs, the inner 

 webs becoming a whitish silver grey, and forming a broad stripe of 

 that colour down the back. 



