532 



MR. A. H. GARROD ON THE 



[June 3, 



thirteen and the right ten complete rings above the commence- 

 ment of the syrinx. Each semisyrinx, as it may be termed, is 

 formed on the same principle as that of the combined organ in most 

 of the non-singing birds. Taking for description that of the left 

 side in the specimen figured, it is there found that the thirteenth 



Fig. 3. 



Front view of the syrinx of Stcatornis. 



bronchial ring is complete, though considerably flattened from 

 side to side ; the fourteenth is not complete in the middle of its 

 inner surface, it is a little longer from before backwards than the one 

 above, and not so long as the one following it. The fifteenth is only 

 a half ring, its inner portion being deficient ; it is slightly convex 

 upwards, and articulates, both at its anterior and posterior ends, with 

 the fourteenth incomplete ring and the sixteenth half ring. The 

 sixteenth half ring is concave upwards, and so forms an oval figure 

 in combination with the one above, which is filled with a thin mem- 

 brane, to form part of the outer wall of the bronchus. There is a 

 membrane also between the ends of these and the succeeding half 

 rings, which completes the tube of the bronchus internally. The 

 half rings which follow the sixteenth reduce in size, and are con- 

 siderably smaller before they reach the lung. The lateral muscle of 

 the trachea extends down the outer side of each bronchus, to be 



