254 



ANATOMY OF THE RABBIT 



abdominal portion of the aorta, the inferior caval vein, and the 

 sympathetic trunks. If the inferior cava does not contain blood, 

 its tributaries should be cleared first, in order to keep them from 

 being damaged; otherwise the branches of the aorta should first 

 be traced. The anterior portion of the inferior cava has been re- 

 moved with the liver. 



The abdominal portion of the aorta, described as the abdominal 

 aorta (aorta abdominalis) extends from the hiatus aorticus of 

 the diaphragm to the seventh lumbar vertebra, where it is re- 

 placed by the paired common iliac arteries. It passes back- 

 ward in a median position along the ventral surfaces of the 

 bodies of the vertebrae. Its primitive continuation backwards 

 on the sacrum and the caudal vertebrae is represented by the 

 greatly reduced median sacral artery. 



The branches of the vessel are distributed in two series: (1) 

 visceral branches (rami viscerales) to the parts of the digestive 

 tube and the urinogenital or- 

 gans; and (2) parietal bran- 

 ches (rami parietales) to the 

 body-wall. 



The visceral branches 

 comprise the paired renal and 

 spermatic arteries, and the 

 unpaired coeliac, superior 

 mesenteric, and inferior 

 mesenteric arteries, which 

 have already been traced. 



The parietal branches 

 comprise: 



(a) The superior phrenic 

 arteries (aa. phrenicae 

 superiores), very small 

 vessels arising by a com- 

 mon trunk in the hiatus 

 aorticus and passing to 



the diaphragm (usually seen better on the right side). 



(b) The suprarenolumbar artery (a. suprarenolumbalis), arising 



Fig. 101. Plan of the pelvic blood-vessels. 

 .Arteries: a, aorta; aei, inferior epigastric; 

 af, femoral; ah, hypogastric; ahm, middle 

 haemorrhoidal; ai, sciatic; aic, common iliac; 

 aie, external iliac; ail, iliolumbar; ao, ob- 

 turator; as, sacral; au, umbilical. Veins: vci, 

 inferior cava; vf, femoral; vh, hypogastric; 

 vh', common hypogastric; vie, external iliac; 

 vil, iliolumbar. 



