. The development of the human body : a manual of human embryology. Embryology; Embryo, Non-Mammalian. DEVELOPMENT OF THE ARTERIAL SYSTEM 241 branches* passing dorsally on either side of the pharynx. The branches of each side then unite to form a paired dorsal aorta (dAr, dAs) which extends caudally and is continued into the belly-stalk and so to the chorion as the umbilical arteries (Au). There is as yet no sign of vitelline arteries passing to the yolk-sack, again an indication of the subservience of the vitelline to the chorionic circulation in the human Fig. 146.—Diagram showing t
. The development of the human body : a manual of human embryology. Embryology; Embryo, Non-Mammalian. DEVELOPMENT OF THE ARTERIAL SYSTEM 241 branches* passing dorsally on either side of the pharynx. The branches of each side then unite to form a paired dorsal aorta (dAr, dAs) which extends caudally and is continued into the belly-stalk and so to the chorion as the umbilical arteries (Au). There is as yet no sign of vitelline arteries passing to the yolk-sack, again an indication of the subservience of the vitelline to the chorionic circulation in the human Fig. 146.—Diagram showing the Arrangement of the Blood-vessels in an Embryo mm. in Length. Au, Umbilical artery; All, allantois; Ch, chorionic villus; dAr and dAs, right and left dorsal aortae; Vu, umbilical veins; Ys, yolk-sack.—(From Kollmann after Eternod.) In later stages when the branchial arches have appeared the dorsally directed arteries are seen to lie in these, forming what are termed the branchial arch vessels, and later also the two dorsal * Evans (Keibel-Mall, Human Embryology, Vol. 11, 1912) considers two of these branches to be probably plexus formations rather than definite stems, since there is evidence to indicate that only one such stem exists at such an early stage of development. 16. 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 McMurrich, J. Playfair (James Playfair), 1859-1939. Philadelphia : P. Blakiston's son & co.
Size: 1791px × 1395px
Photo credit: © Paul Fearn / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookautho, bookcentury1900, bookdecade1910, booksubjectembryology
