The intricately and prodigiously looped system of veins and aeries that lie on the surface of the epididymis is known as :

Pectiniform septum- The testicular veins join to form intricately & prodigiously looped venous nentwork, the pampiniform plexus, consisting of 8-12 veins lying anterior to ductus deferens & lying on the surface of epididymis and surrounding the testicular aery in the spermatic core. It is the pa of thermoregulatory system of the testisBoth testicular vein originate in pempiniform plexus; left testicular vein drains into left renal vein & right testicular vein drain into inferior vena cave.