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lows: The external iliac veio on either side ascends first to the inside 

 then behind its corresponding artery. The internal iliac vein, at first 

 lying along the inner aspect of its corresponding artery, proceeds up- 

 ward behind the common iliac artery; here union of the iliac veins 

 takes place. This arrangement also holds good for the internal iliac 

 veins of either side. 



The renal veins in this specimen afford an interesting example of 

 persistence of the primitive condition of the intermediate visceral 

 segmental veins from which they have originated. Each pours its 



Diagram to show persistence of the post-renal portions of the cardinal veins (nearly 

 ^/g nat. size). 



blood separately into the cardinal of its own side, while the two renal 

 veins are of equal length as contrasted with the considerably longer 

 left renal vein found normally in the permanent arrangement of the 

 venous system after birth. 



The spermatic veins also exhibit a somewhat primitive condition 

 of the intermediate visceral segmental veins from which they originate, 

 each opening into its respective cardinal somewhat obliquely as con- 

 trasted with the decidedly asymmetrical arrangement which maintains 

 after birth, namely the oblique union of the right spermatic with the 

 inferior vena cava and the almost right-angled union of the left, 

 spermatic with the left renal vein. 



