The pouches and septum were now removed and the position of the hepatic tract determined. It rested upon the incurved borders of the ensiform cartilages (see Fig. 15), and as the subject lay on the table with the “posterior” surfaces of the band exposed (Fig. 11) the hepatic tract was slightly arched. It measured three inches in length, was compressed, and measured six lines wide and three lines thick. The tract arose from the livers at the same point—namely, directly above the longitudinal fissure, having more fulness on the side of the right than of the left lobe. The round ligament, as it passed out of the longitudinal fissure of each liver, was placed beneath and a little to the left of the tract. [Illustration Figure 9: Fig. 9. The septum viewed from Chang’s side. A. The orifice of umbilical pouch of Chang. B. The orifice of the hepatic pouch of Chang. C. Suspensory ligament of Chang containing umbilical pouch of Eng. ] [Illustration Figure 10: Fig. 10. The septum viewed from Eng’s side. A. The orifice of the umbilical pouch of Eng. B. The orifice of the hepatic pouch of same. C. Suspensory ligament of Eng containing the umbilical pouch of Chang. ] 3. _The vascular structures of the band_ were as follows:— The livers being united, it was found that a colored injection thrown into the portal vein of Chang passed into the liver of Eng. A careful dissection of the blood vessel (Fig. 11, C) proved it to be a terminal twig of the portal system of Chang. It was of the thickness of a No. seven catheter, French scale, gradually diminished in size, and was lost toward the centre of the band. It did not pass as such across the band, but appeared to break up into minute branches before reaching the liver of Eng. At the same time there was undoubted distension of the portal capillaries with the colored fluid under the capsule of the dorsal surface of the right lobe of Eng’s liver, one and one-half inches from the band. Examination of the branches of the mesenteric veins of Eng revealed the curious fact that some of them had received the injection. This had not been transmitted through the liver, for the portal vein at the transverse fissure was empty, but through a distinct extra-hepatic portal track, which was found lying under the peritoneum beneath the position of the hepatic pouches, and in association with the umbilical pouches. This vessel began by relatively large radicals towards Chang’s side, became larger as these encroached on Eng’s side, and was finally received within the portal system of Eng’s body, as a tributary to its mesenteric vein. [Illustration Figure 11: Fig. 11. The surface, C. R., E. L., with pouches removed to display the hepatic tract. A. Liver of Chang. B. Liver of Eng. C. Portal vessel of Chang. D, D. Minute branches of hepatic artery.