OF THE TRUMPETER BIRD. 
529 
verted, is shewn at Fig. S., and still better at Fig. 3. Plate 
XVI. The drawing, Fig. 1., is of the size of nature; the 
parts are seen in their true position, having been taken while 
the subject was recent, and before the tubes were displaced. 
The glottis or upper larynx of the Trumpeter presents 
nothing remarkable. The general form of the trachea is 
conical, — a shape (as remarked by Cuvier in his admirable 
Dissertation on the Voice of Birds) which is usually the 
index of an unmusical voice ; whereas the cylindrical tra- 
chea belongs to songsters, and other birds possessing what 
he calls une mixfiutee. The windpipe of the Trumpeter 
is very slightly dilated, about an inch before it enters the 
thorax, when it contracts a little, and rather suddenly. 
Each ring, when closely examined, consists of two carti- 
lages joined firmly together at the sides of the trachea,—- a 
structure not readily detected, until the windpipe has been 
macerated in water for some time. The rings are firm, and 
lie close to each other ; yet the trachea is capable of con- 
siderable elongation, from the simultaneous action of the 
mylo -hyoideus, ster7io-tr ache alls, and upsih - irachealis 
muscles. On emerging from the thorax, the trachea first 
passes along the front, and then to the right side of the 
lower curvature of the neck, for about four inche;^ ; when 
it again stretches toward the forepart of the neck, before it 
reaches the head of the bird. 
The lowest cartilage of the trachea is firm, almost bony ; 
its lateral portions have an obtuse triangular form, with 
minute projections at the extremities, where they meet the 
bony septum of the lower larynx. This septum is thin, 
and about ^^^th of an inch in depth, dividing the extremity 
of the air-tube into two acutely oval foramina, rather more 
than 0.3 inch in length, and 0.1 inch in their greatest dia- 
meter. Each side of the septum supports a thin, strong, 
membranous plate or fringe, about 0.1 inch in breadth, 
VOL. V. L 1 
