FIGURES 134 AND 135 



134 Same, section 18. 



135 Same, section 19. 



3 Right precaval vein. 



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. 

 9 Trachea. 

 10 Pulmonary artery. 

 22 Vagus. 



