454 Mr. J. G. Millais on Change to 



Next we come to method No. II., -wherein we notice a 

 bird assuming its summer dress by means of a partial moult, 

 and also by many of the old winter feathers themselves 

 changing colour. 



Amongst birds that may be said to have a distinct summer 

 plumage, this is, perhaps, the commonest form of change, of 

 which the families of the Grouse and Grebes are good ex- 

 amples. But, inasmuch as a bird like the Ptarmigan shows 

 the change more slowly and far more elaborately, the case of 

 the Sclavonian Grebe {Podicipes auritus) is quicker and 

 simpler. 



In the spring of 1886 I was equally fortunate in obtaining 

 a fine series of Sclavonian Grebe in process of change and in 

 full summer plumage. Unlike the case of the Long-tailed 

 Duck, which, one may say, stays late on our coast one season 

 in every four, the Sclavonian Grebes turn northward very 

 regularly, passing the Orkneys, generally without stopping, 

 at the end of March. Only once before has Mr. Begg, the 

 old Stromness naturalist, known the Sclavonian Grebes to 

 have been blocked, as they were in 1886, by adverse winds. 

 I found them very shy, as all water-birds are when in course 

 of actual migration, and I had to exercise the greatest caution 

 in sailing down on one of them, for they were generally 

 alone. Unless a bird is actually feeding, it can seldom be 

 approached nearer than 100 yards, while, under any circum- 

 stances, if a Shag or a Black Guillemot rose within any 

 distance at which it could be plainly seen, the Grebe would 

 get up at once and fly out of sight. After several failures, 

 due to these causes, 1 used a small sailing-boat in preference 

 to the punt, of which, curiously enough, they seemed sus- 

 picious, and I was then very successful, getting almost 

 every Grebe I saw, until my series was complete. 



The change of plumage begins to show itself in a rosy 

 blush on the upper front of the neck and in the feathers 

 above the ears, after which the red gradually spreads down 

 the neck. Any further verbal explanation of this change is 

 unnecessary, as by reference to the coloured figures (Plate X. 

 figs. 1-7) it will be seen how the old feathers change their 



