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Show 1905.J OF THE YELLOW-THROATED LIZARD. 259 The second point concerns the relationship of the two umbilical ligaments to veins entering the liver. A dissection of both specimens of Gerrhosaurus shows that the anterior abdominal vein enters the liver in the region of the left umbilical ligament (c in text-figs. 33, 34), and that the epigastric vein is similarly connected with the right umbilical ligament. Precisely the same relationship holds for Macroscincus cocteaui. Inasmuch as the anterior abdominal vein joins the portal vein, the latter might Text-fig. 33. Text-fig. 34. Text-fig. 33.-Liver o f Gerrhosaurus flavigularis, ventral aspect. a. Attachment o f umbilical ligament; b. Seam indicating course o f embryonic umbilical vein (? ); c. Left half o f umbilical ligament; Ant.Abd. Anterior abdominal vein; Ep. Epigastric vein; g.b. Gall-bladder. Text-fig. 34.- Liver o f a second example o f Gerrhosaurus flavigularis, ventral aspect. Lettering as in text-fig. 33. be regarded as fixing this point were it not for the conditions observable in Macroscincus cocteaui. In that lizard the portal vein, immediately in front of the region where it has, as have the portal veins of other lizards, a spiral twist, divides into two branches, which enter the liver in a line with each part of the divided umbilical ligament. As to the relationship between the divided 17* |