;39(> Explanation of the Plates. 



Tab. XIII. 



Trachea and Clavicles of the Semipalmated Goose {Anas semi- 

 palinala Lath.), one-third less than the natural size. 



]\Iale. — a. a. Conv^olutions of the trachea not found in the second 

 specimen {tab. 14.). b. Right clavicle, common form. 

 c. Left clavicle, enlarged. 

 fl. Projecting point for the attachment of the tube of the 

 trachea. 



c.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 ala) to be inserted on the upper 

 part of the humerus. 



Tab. 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, 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 alee) to be inserted on the upper 

 part of the humerus. 



Tab. XV. 



a. Part of the trachea of the Muscovy Duck {Anas Moschata 



Linn.). 



b. Free hind-toe of the Ducks of the first division. 



c. d. Lower 



