V0l 'r9U Vm ] Brewster, Nuptial Plumes of Bitterns. 93 



were more than twice that distance apart. As was the case yester- 

 day they carried their bodies very low and at times so flattened 

 to the ground that they resembled big, swift-crawling tortoises 

 rather than birds, as they wound in and out among the tufts of 

 grass for on this occasion they pursued devious courses which 

 usually ended near the starting point. They did not seem to be 

 looking for food but rather to be inspired by restlessness and 

 also by a spirit of rivalry. As both "pumped" at frequent inter- 

 vals I concluded that both must be males. There was much 

 connected with their behavior which suggested that they were 

 chiefly engaged in "showing off" apparently to each other, solely, 

 for if there was a female anywhere near at hand we failed to see 

 her. Whenever one of them "pumped" the other was sure to 

 respond within two or three seconds, sometimes facing his rival, 

 sometimes turning in another direction. During most of the time 

 when they were in the marsh together both birds showed the white 

 which we saw yesterday but when one of them finally flew away the 

 other ceased altogether to display it although we had him in view 

 for some twenty minutes longer during which time he "pumped" 

 repeatedly. The white was seen much better and for a longer 

 period to-day than yesterday and I was able to check, as well as 

 supplement, my own observations by those of Purdie and Gilbert 

 both of whom were with me the whole time and paying equally 

 critical attention to the matter. At first we disagreed with re- 

 spect to certain minor details but all such difference of opinion 

 was finally harmonized and what I am about to record is now 

 subscribed to by all three of us. 



The white first appears at or very near the shoulders of the 

 folded wings and then expands, sometimes rather quickly (never 

 abruptly, however) but oftener very slowly until, spreading simul- 

 taneously from both sides, it forms two ruffs apparently almost 

 if not quite equal in length and breadth to the hands of a large 

 man but in shape more nearly resembling the wings of a grouse or 

 quail held with the tips pointing sometimes nearly straight upward, 

 sometimes more or less backward, also. As they rise above the 

 shoulders these ruffs spread toward each other at right angles to 

 the long axis of the bird's body until, at their bases, they nearly 

 meet in the centre of the back. Sometimes they are held thus 



