248 



THE VASCULAR SYSTEM. 



(3) The dorso-lumbar vein (1'ena dorso-lumbalis), (Fig. 163 a'} is 

 a vein (or more usually several) arising by twigs in the dorsal and 

 outer walls of the abdomen it joins the renal portal vein opposite 

 the kidney. 



(4) The oviducal veins (Fig. 163 o?;) are irregular veins from 

 the oviducts, which open either into the dorso-lumbar vein, or into 

 the renal portal vein. 



b. The hepatic portal system. 



The liver receives blood from two sources : (i) from the hind- 

 limbs by means of the 

 anterior abdominal 

 vein, and (2) from the 

 alimentary canal by 

 the hepatic portal vein. 



The anterior ab- 

 dominal vein ( Vena 



Fig. 164. 



alj, 164 Va) is formed, 

 a little in front of the 

 symphysis piibis, by 

 the union of the two 

 pelvic veins. It courses 

 forwards . along the 

 middle line of the 

 ventral body-wall un- 

 til opposite the liver, 

 where it ascends and 

 divides into three 

 branches, of which 

 two enter the right 

 and left lobes of the 

 liver respectiveyl. The 

 third, the Ramus de- 

 scendens, joins the 

 hepatic portal vein. 

 The anterior abdomi- 

 nal vein receives the 

 following veins : 

 a. The vesical vein (Vena vesicalis), (Fig. 163 T'v) ; a median 

 vein arising in the groove between the lobes of the bladder from 

 lateral branches, which extend outwards on the bladder. This vein 



Veins of the liver. 



A A Auricles. 



aa Right and left branches of 



anterior abdominal vein. 

 6 Ramus descendens. 

 c Vena bulbi (Vena cardiaca). 

 D Intestine. 

 G Gall-bladder. 

 L.I. Left lobe of liver. 

 L.r. Right lobe of liver. 



Hepatic portal vein. 



Intestinal veins. 



Gastric veins. 



Sinus venosus. 



Ventricle. 



Anterior abdominal 



vein. 



V.c.i. Posterior vena cava. 

 v.h. Hepatic veins. 



