THE ANATOMY OF BIRD-SONG. 109 



gross error in the conclusions arrived at by 

 writers upon the subject of bird-song. The 

 harsh croaking notes, when closely observed, 

 are found actually to begin as if the bird were 

 going to whistle ; but the sounds are arrested 

 by the tongue and mouth-roof, and flung back 

 into the throat, so to speak, where they are 

 distorted, broken, and specialized into a char- 

 acteristic rasping gurgle-phrase, which at a 

 distance is taken for a genuine voice-effect, 

 because of the peculiar jar or vibration of the 

 throat and mouth membranes communicated 

 to the reflected air-column above and posterior 

 to the glottis. 



It is quite the habit of ornithologists to allege 

 that a rook or a shrike has just as good a 

 vocal organ as a mocking-bird or a wood- 

 thrush, and, viewing the syrinx as such 

 organ, doubtless they are right; the error re- 

 sides in the point of view. The very fact that 

 a logger-head shrike with its preposterous 

 rasp- voice has a really larger and better syr- 

 inx than the robin, or the mocking-bird, or 

 any other sweet singer, ought of itself to give 

 rise to some doubt as to whether the voige- 

 organ of the birds has been rightly located by 

 the anatomists. Prof. Huxley's description 

 of the bird-syrinx is admirable in every way ; 

 no one can find fault with it from the anatomi 

 cal point of view ; but he assumes the physi- 

 ological part of the problem, or rather takes 

 the function of the so-called organ as granted 

 without proof. It is clear to my mind that 

 he was led to do this by Macgillivray's brill- 

 iant treatment of the subject, and Parker 

 all but admits that he has submitted to the 

 same influence. Dr. Elliot Coues simply adopts 

 the reasoning and presents the plates of Mac- 

 gillivray's work. Indeed it appears, so far 

 as I know, that no biologist since Macgillivray 



