THE URINARY SYSTEM: KIDNEYS 



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From the examination of four foetal kidneys (two from a 3-0 m. foetus and two from a 

 i-8 m. foetus), injected with carmine, it has been found that while the vascular arrange - 



Fig. 3 1 • Diagram illustrating the disposition of the main arteries, veins and urinary ducts within the kidney. 

 (Arteries in red, veins shaded and urinary ducts dotted.) 



ment within the organ shows large individual variations, it is nevertheless always built 

 on a common plan. This is illustrated diagrammatically in Fig. 31. The renal artery, on 

 entering the kidney, is found to exhibit three branches, from which smaller ones ramify 



