80 BULLETIN 135, UNITED STATES NATIONAL MUSEUM 



wondering whether after all our eyes might not have deceived us. It occurred 

 to me that the flickering shadows from the swaying flags might have created the 

 illusion and that the rippling water with its broken reflections possibly made it 

 more complete; but another gentle breeze gave us an opportunity to repeat the 

 observation with both these contingencies in mind and there was no escape from 

 the conclusion that the motion of the bittern was actual, not due to shadows or 

 reflections, or even to the disturbance of the plumage by the wind itself. The 

 bird stood with its back to the wind and its face toward us. We were within a 

 dozen yards of it now and could see distinctly every mark of its rich, brown, 

 black, and buff plumage, and yet if our eyes were turned away for an instant it 

 was with difficulty that we could pick up the image again, so perfectly did it 

 blend with the surrounding flags and so accurate was the imitation of their wav- 

 ing motion. This was repeated again and again, and when after 10 or 15 min- 

 utes we went back to our work, the bird was still standing near the same spot 

 and in the same rigid position, although by almost imperceptible steps it had 

 moved a yard or more from its original station. 



The most characteristic performance of the bittern, for which it is 

 best known and from which some of its names have been derived, is 

 one in wh.ich it is more often heard than seen, its remarkable "thunder- 

 pumping" performance. It is more frequently and more constantly 

 heard in the spring, as a part of the nuptial performance, but it may 

 be lieard at any time during the summer and rarely in the fall. It 

 is only within comparatively recent years that the mystery of this 

 disembodied voice of the marshes Ixas been thoroughly cleared up by 

 actual observations; many erroneous theories had previously been 

 advanced, as to how the sound was produced. Anyone who has ever 

 skinned a male bittern in the spring, might have noticed that the 

 skin of the neck and chest becomes much thickened and reinforced 

 with muscidar and gelatinous tissues, so that it can form a bellows 

 for producing the loud, booming sounds. These notes have been lik- 

 ened to the sound made by an okl wooden pump in action and to the 

 sound made by driving a stake into soft ground; the fancied simi- 

 larity of the bittern's notes to two such different sounds is not so 

 much due to different interpretations by observers, as to the fact 

 tliat tliere are two quite distinct renderings of the notes, by different 

 birds or by the same bird under different circumstances. Mr. Brad- 

 ford Torrey (1889) has published some valuable notes on this subjecc,. 

 from which I quote, as follows: 



First the l)ird opens his bill quickly and shuts it with a click; then he does the 

 same thing again, with a louder click; and after from three to five such snap- 

 pings of the beak, he gives forth the familiar tris\ilabic pumping notes, repeated 

 from three to eight times. With the preliminary motions of the bill the breast 

 is seen to be distending; the dilatation increases until the pumping is well under 

 way, and as far as we could make out, does not subside in the least until the 

 pumping is quite over. It seemed to both of us that the bird was swallowing 

 air — gulping it down— and with it distending his crop; and he appeared not to 

 be able to produce the resonant pumping notes until this was accomplished. It 

 should be remarked, however, that the gulps themselves, after the first one or 

 two at least, gave rise to fainter sounds of much the same sort. The entire per- 



