. A laboratory manual and text-book of embryology. Embryology. PRIMITIVE BLOOD VASCULAR SYSTEM 269 on either side of the brain they join the vitello-umbilical trunk. In embryos of 23 somites the posterior cardinals are present. They lie dorsal to the nephrotomes and, running cranially, join the anterior cardinal veins to form the common cardinal veins. Owing to the later enlargement of the sinus venosus, the proximal portions of the venous trunks are taken up into its wall and thus three veins open into each horn of the sinus venosus: (1) the umbilical veins from the chorion; (2) the l& Ce
. A laboratory manual and text-book of embryology. Embryology. PRIMITIVE BLOOD VASCULAR SYSTEM 269 on either side of the brain they join the vitello-umbilical trunk. In embryos of 23 somites the posterior cardinals are present. They lie dorsal to the nephrotomes and, running cranially, join the anterior cardinal veins to form the common cardinal veins. Owing to the later enlargement of the sinus venosus, the proximal portions of the venous trunks are taken up into its wall and thus three veins open into each horn of the sinus venosus: (1) the umbilical veins from the chorion; (2) the l& Cervical artery Pulmonary artery Vertebral artery Vena capitis media. Com. card- mat vein Porsal aorta Caudal artery Umbilical artery 'Inf. mesenteric artery Fig. 264.—Arteries and cardinal veins of the right side in a mm. human embryo (modified after Ingalls). H, heart; /, II, III, IV, and VI, first, second, third, fourth, and sixth aortic arches. vitelline veins from the yolk-sac; (3) the common cardinal veins from the body of the embryo. The descending aortas, have now fused caudal to the seventh intersegmental arteries and form the single dorsal aorta as far caudad as the origins of the um- bilical arteries. Of the numerous vitelline arteries, one pair are prominent and they fuse to form the single vessel which courses in the mesentery and later forms the superior. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Prentiss, Charles William, 1874-1915. Philadelphia, London, W. B. Saunders
Size: 1550px × 1612px
Photo credit: © The Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1910, booksubjectembryology, bookyear1
