postrenal

The portion of the right subcardinal behind this cross communication disappears, while that in front, i.e., the prerenal part, forms a connection with the ductus venosus at the point of opening of the hepatic veins, and, rapidly enlarging, receives the blood from the postrenal part of the right cardinal through the cross communication referred to.

V. Angiology. 3. Development of the Vascular System 1918

The postrenal segment of the left cardinal disappears, with the exception of the portion between the spermatic and renal vein, which is retained as the terminal part of the left spermatic vein.

V. Angiology. 3. Development of the Vascular System 1918

The spermatic (or ovarian) vein opens into the postrenal part of the corresponding cardinal vein.

V. Angiology. 3. Development of the Vascular System 1918

In this manner a single trunk, the inferior vena cava (Fig. 480), is formed, and consists of the proximal part of the ductus venosus, the prerenal part of the right subcardinal vein, the postrenal part of the right cardinal vein, and the cross branch which joins these two veins.

V. Angiology. 3. Development of the Vascular System 1918