FIGURES 208 AXD 209 



20S Same, section 17. 

 209 Same, section 19. 



2 Intersegmental arteries. 



3 Right azygos vein, thoracic portion. 



4 Atrophying embryonal vein, forming kernel in interior of develop- 



ing and replacing lymphatic vein. 



5 Extraintimal or perivenous lymphatic space surrounding degener- 



ating embryonal vein. 

 (3 Left azygos vein, thoracic position. 



7 Aorta. 



8 Oesophagus. 



15 Interazygos venous plexus. 



