FIGURES 144 and 145 



144 Same, section 34. 



145 Same, section 35. 



3 Right precaval vein. 



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



oping and replacing lymphatic space. 



5 Extraintimal or perivenous lymphatic space .surrounding degen- 



erating embryonal vein. 



6 Precardinal or precava of left side. 



7 Aorta. 



8 Oesophagus. 

 Trachea. 



Pulmonary artery. 

 Peritracheal venous plexus. 

 Vagus. 



