THE THORAX. 



199 



Dissect the following structures and study them carefully : 



1. The subclavius muscle and the costo-clavicular ligament. 



2. The external intercostal muscles and their fasciae. 



3. The internal intercostal muscles and their fasciae. 



4. The intercostal fasciae, internal, middle, and external. 



An interartieular 

 ligament 



The plate of flbro- 

 cartilage between 

 manubrium and 

 meso -sternum 



SIXTH RI3 H 



SEVENTH RIB 



FIG. 139. THE STERNUM. 

 (Left side, showing ligaments ; right side, the synovial cavities/ 



5. The anterior chondro-sternal ligaments. 



6. The anterior common sternal ligament of periosteal derivation. 



7. The scalenus anticus, inserted into the scalene tubercle of the first rib. 



8. The scalenus medius, inserted into the scalene depression of the first rib. 



9. The subclavian groove, between the scaleni muscles on the first rib. 

 10. The groove for subclavian vein on the outer surface of the first rib. 



