GENERATION AND DEVELOPMENT 



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/it.lf... 



fl.V.C 



u.c 



Fig. 253. — Diagram of the Fcetal Circulation (Ellenberger). 



u.v., Umbilical vein; d.v., ductus venosus ; pt.v., portal vein; /., liver; v.h., 

 hepatic veins ; p.v.c, posterior vena cava ; r.a., right auricle ;/.o., foramen 

 ovale ; r.v., right ventricle ; p.a., pulmonary artery ; d.a., ductus arteriosus ; 

 La., left auricle ; l.v., left ventricle ; a., the aorta ; a.a„ arch of aorta ; ant.a., 

 anterior aorta ; i.v., innominate veins ; a.v.c, anterior vena cava ; po.a., 

 posterior aorta ; i.a., iliac artery ; h.a., hypogastric artery ; u.a., umbilical 

 arteries ; i.ve., iliac veins ; h.v., hypogastric veins ; u.c, umbilical cord. 



The diagram actually represents the fcetal circulation in ruminants ; to make it 

 applicable to the horse the ductus arteriosus (d.v.) must be supposed to be 

 removed ; the whole of the blood then traverses the liver by the union of 

 the umbilical vein (u.v.) with the portal vein (pt.v.). The arrows indicate 

 the course taken by the blood. Observe that the stream entering the right 

 auricle divides, part passing into the right ventricle, and part into the left 

 auricle through the foramen ovale (f.o.). 



