390 Explanation of the Plates. 
Tas. XIII. 
Trachea and Clavicles of the Semipalmated Goose (Anas semi- 
palmata Lath.), one-third less than the natural size. 
Male.—a.a. Convolutions of the trachea not found in the second 
specimen (fab. 14.). b. Right clavicle, common form. 
c. Left clavicle, enlarged. 
d. Projecting point for the attachment of the tube of the 
trachea. 
e.e. Cavities to receive the head of each humerus. f. f. Aper- 
ture formed by the junction of the furcula, clavicle and 
scapula, through which passes the tendon of the second 
pectoral muscle (levator ale) to be inserted on the upper - 
part of the humerus. 
Tas. XIV. 
‘Trachea and Clavicles of the Semipalmated Goose (Anas semi- 
palmata Lath.), one-third less than the natural size. 
Male.—a.a. Part of the sternum. b. Left clavicle, common 
form. | 
c. Right clavicle, enlarged. d. Projecting point for the at- 
tachment of the tube of the trachea. 
e.e. Cavities to receive the head of each humerus. - Sf. Aper- 
ture formed by the junction of the furcula, clavicle and 
scapula, through which passes the tendon of the second 
pectoral muscle (levator ale) to be inserted on the upper 
part of the humerus. 
Tan. X V. 
a. Part of the trachea of the Muscovy Duck E nas Moschata 
Linn.). 
b. Free hind-toe of the Ducks of the first division. 
c.d. Lower 
