FIGURES 210 AND 211 



210 Same, section 21. 



211 Same, section 22. 



1 Sympathetic nerve. 



3 Right azygos vein, thoracic portion. 



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



ing and replacing lymphatic space. 



5 Extraintimal or perivenous lymphatic space surrounding degener- 



ating embryonal vein. 



7 Aorta. 



8 Oesophagus. 



15 Interazygos venous plexus. 



