50 BULLETIN 14 6;, UNITED STATES NATIONAL MUSEUM 



Spring. — Apparently the ruff migrates chiefly by night and in 

 this connection it is noticeable that the period of its greatest activity 

 in the breeding season is during the twilight of the early morning 

 hours. Naumann (1887) states 'that the first birds to arrive are 

 the young of the preceding year, and that the adult males are the 

 next to follow while they in turn are succeeded by the old females. 

 Owing to the enormous development of the feathered ruff from which 

 the species derives its names, the males are readily distinguished 

 during the breeding season even in flight and on the ground can be 

 recognized at almost any distance. 



Courtship. — The breeding habits of the ruff are so remarkable 

 that it is necessary to treat of them in considerable detail. When 

 the males reach the breeding ground they are in full breeding plum- 

 age, the bare skin of the face being covered with bright yellow 

 warts, while a disk of feathers protects the neck and two tufts 

 project from each side of the head. The extraordinary variation in 

 the coloring of these feather adornments renders it possible to 

 identify individual birds, as it is rare to see two with even approxi- 

 mately similar coloring, and this enabled Mr. Selous (1906) to make 

 the valuable observations which are referred to below. 



Where ruffs are common, as in North Holland, one finds from 

 time to time bare areas of ground where the grass has been worn 

 away in patches. They are the playing grounds of the ruffs, and 

 were known in England technically as " hills." During the daytime 

 they are resorted to from time to time by the male birds, which 

 may often be seen sparring with one another, but the significance 

 of these meetings was little understood until Edmund Selous (1906) 

 spent a fortnight in the spring of 1906 in Holland, during which 

 he concealed himself in a hide which commanded a good view of 

 the " hill " at close quarters, and was often on the watch before 

 daylight. The diary of his observations was first published in the 

 Zoologist for 1906 and 1907, and is too lengthy and discursive to be 

 reproduced here, but in the following condensed account most of the 

 essential facts have been preserved. The " hill " under observation 

 was roughly about 10 paces by 6, with 11 distinct patches where 

 the grass had been worn bare, besides a couple of others less plainly 

 marked. There were other similar " hills " in the neighborhood, all 

 much alike, placed on dry ground, in the neighborhood of marshes. 

 They are resorted to year after year, and bear traces of excrement 

 from previous seasons, while the grass is much worn away owing 

 to the presence of the birds. Some of the Dutch " hills " are quite 

 close to or actually in the way of paths, and the birds when disturbed 

 by passers-by will return to the ground within a few minutes. Like 

 many other Dutch birds they show much indifference to the presence 



