18/8.] ON THE TRACHEA OF TANTALUS AND VANELLUS. 625 



7. On the Trachea of Tantalus loculalor and of Vanellus 

 cayennensis. By A. H. Garrod, M.A., F.R.S. 



[Eeceived May 21, 1878.] 



In his • Beitrage zur Naturgeschichte von Brasilien,' Maximilian, 

 Prince of Wied 1 , describes briefly and figures the lower end of the 

 trachea of Tantalus loculator. A male specimen of the species 

 having recently died in the Society's Gardens, I take the opportunity 

 of more minutely pointing out its peculiarities and of comparing it 

 with T. ibis, the windpipe of which, with its elaborate convolutions, 

 1 have had the opportunity of bringing before the notice of the 

 Society upon a previous occasion 2 . 



In Tantalus loculator the trachea is not elongated as it is in T. ibis ; 

 nevertheless it is peculiarly modified, and differs in detail from that 

 of any bird with which I am acquainted, although its plan of con- 

 struction is perfectly Ciconiine. 



The seventy-eight lowermost rings of the trachea are those which 

 are modified, the rings above them being quite typical, of average 

 depth, notched in front as well as behind, and overlapped to produce 

 the well-known zigzag markings on the surface. 



With the exception of the last one, all the modified rings are much 

 reduced in depth ; and of them the sixty-one upper rings are com- 

 pressed from side to side and bent sharply in front, whilst the lower 

 seventeen are somewhat flattened from before backwards and sharply 

 bent laterally, the general effect of which is to produce a lateral flat- 

 tening and an anterior carination of the whole tube opposite the 

 fifty-one rings, as well as an antero-posterior flattening with a lateral 

 carination in the part below. The change from the superior unmodi- 

 fied tube to the laterally compressed portion is somewhat abrupt, as 

 is that between the two differently modified parts. In figure 1 a 

 (p. 626) the front view of the lower end of the trachea is repre- 

 sented, figure b giving a side view of the same. 



The powerful sterno-tracheal muscles leave the wind- pipe opposite 

 the middle of the laterally flattened portion of the tube ; and a few 

 muscular fibres from their anterior margin are continued downwards 

 for a short distance, but not nearly to the last ring, they being lost 

 upon the sides of the trachea. 



The arrangement above described is only an exaggeration of what 

 is found in Ciconia alba, in which species the lowermost nine-and- 

 twenty tracheal rings are extremely shallow and slender, the fifteen 

 above the bifurcation of the bronchi being antero-posteriorly flattened, 

 the fourteen above them being in no wise peculiar except for their 

 slenderness. In C. alba there is, however, a small prolongation up- 

 wards of the lateral portions of the three lowermost tracheal rings, 

 which forms a consolidated triangular process on each side, overlap- 

 ping the next few rings, and looking extremely like rudiments of the 



1 Band iv. p. 687, tab. 1. figs 7 and 8. 



2 P. Z. S. 1875, p. 298. 



