FIGURES 212 AND 213 



212 Same, section 23. 



213 Same, section 28. 



1 Sympathetic nerve. 



3 Right azygos vein, thoracic portion. 



4 Atrophying embryonal vein, forming kernel in interior of developing 



and replacing lymphatic space. 



5 Extraintimal or perivenous lymphatic space surrounding degenerat- 



ing embryonal vein. 



6 Left azygos vein, thoracic portion. 



7 Aorta. 



8 Oesophagus. 



15 Interazygos venous plexus. 



