On the venous system of the common Indian rat‐snake ptyas mucosus (Linn.)

Abstract

AbstractThe venous system of Ptyas mucosus (Linn.) presents the following features which appear to be hitherto undescribed in Ophidia: (1) Direct connection of the anterior azygos vein with the lateral cephalic vein just behind the head and also its anastomosis with either of the common jugular veins (right or left). (2) Anastomosis of the right and left common jugular veins with the epigastric vein in the neck region. (3) Left common jugular vein larger than the right. (4) Origin of the oviducal sinuses directly from the afferent renal veins and their termination on either side directly into the postcaval. (5) Persistence of the posterior cardinal veins in both the sexes. (6) Opening of most of the branches of the epigastric vein directly into the vena mesenterica in the liver region and of a few only into the right lobe of the liver. (7) Branches from the meso‐rectum contributing to the formation of the vena mesenterica. (8) Opening of some veins into a branch of the epigastric vein lying just behind the heart, which carry blood from the dorsal surface of the right lung, trachea, pericardial wall, and also from the parietal layer of the body wall on the left side.