372 U. S. NATIONAL MUSEUM BULLETIN 211 



and no one can be within range of the birds' voice without being 

 abundantly aware of their presence throughout the entire day. 



The boat-tailed grackle produces one sound, however, which has 

 attracted the study and conjecture of many ornithologists, and 

 without mention of which, no account of the voice would be complete. 

 I speak of the remarkable rolling, or rattling sound so thoroughly 

 characteristic of the "jackdaw." Many have noted it, some have 

 commented on it, but no one who watches or listens to this grackle 

 very long can fail to be impressed by it. Curiously enough, Audubon 

 does not mention it at all, although he could hardly have failed to 

 notice it, and his great friend and collaborator, John Bachman, also 

 omits reference to it. Nuttail however, while not stressing this sound, 

 at least recognized its existence, though he intimates that word of it 

 came to him second-hand for he says (1832) that "some of its jarring 

 tones are said to bear a resemblance to the noise of a watchman's 

 rattle." That this refers to the sound in question is not to be doubted. 



Contemporary writers have used the words "rolling" and "rattling" 

 to describe the sound, but the point in controversy is whether it is 

 instrumental or vocal. A. T. Wayne (1910) says: "A peculiar habit 

 of the male of this species is to perch upon a limb of some tree and 

 with their wings make a loud rolling sound. This peculiar noise is 

 also frequently made while the birds are flying." 



From his observations of the Florida race (see p. 363), Townsend 

 (1927) concluded that the rattle was vocal, not mechanical, and my 

 notes of March 24, 1926, made at Charleston, S. C, explain this: 

 "The bird was seen on a tree in a favorable light within twenty yards 

 and studied with eight power prismatic glasses. After three or four 

 wheezy trills with bill wide open, he would partly close it and appear 

 to gulp and the feathers of the throat vibrated as the guttural rattle 

 was produced. I could see the bill vibrating also, but it did not 

 occur to me then, nor does it seem probable to me now, that the bill 

 made the sounds. The vibration of the throat would seem to point 

 to its vocal origin. Certain parts of the song of the purple martin 

 are very similar to this guttural rattle, and the throat of the bird may 

 in the same way be seen to vibrate. I observed this at Mr. Wayne's 

 home." 



I have watched literally hundreds of boat-tails make this rattling 

 sound and have studied them at very close range, with and without 

 binoculars, in South Carolina, Georgia, and Florida, particularly the 

 latter. While for some time I could not decide whether the sound 

 came from the throat or the clacking of the mandibles, it was per- 

 fectly clear that it was most certainly not produced by the wings. 



On dozens of occasions the rattle sounded with the wings absolutely 

 motionless, not even the slightest vibration of their tips taking place. 



