extraordinary Human Foetus . 135 
9. The pulmonary arteries. 
10. The descending aorta. 
11. Vena cava inferior, terminating in the right heart 
12. Vena cava superior, terminating in the left heart. 
13. A considerable vessel of communication, passing between 
the vena cava superior of the left heart, and the vena cava 
inferior of the right heart. 
14. The umbilical vein. 
15. Ductus venosh 
