Centimeters 



Figure 233. — Diagram of the venous system of C. virginica viewed from the right side. The right demibranch is open 

 and pulled out to show the water tubes and the vessels of the descending and ascending lamellae. The left demi- 

 branch is not visible. Vessels carrying oxygenated blood are shown in solid black; others are open. The diagram 



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FISH AND WILDLIFE SERVICE 



