PLATE XIV. 



FIG. 26. Similar section to 24 through the hyo-opercularis vein. Structure 

 is very similar to the lymphatic trunk, but the red corpuscles greatly predom- 

 inate. X 45- Reduced ^. 



FIG. 27. A diagrammatic transverse section through three pairs of branchial 

 filaments of Polyodon. 



