To this organ the growing foetus is moored by a species of cable, the Umbilical Cord.
How the yolk-sack (umbilical vesicle) is formed is not clear.
They are the Epigastrick, the Umbilical, and the Hypogastrick.
Midwives differ on the point of the moment at which the umbilical cord should be severed.
The somatic stalk together with its contents is known as the umbilical cord.