"Respiratory system of hag, from ventral surface. b., Barbules; m., mouth opening on ventral surface; g., gullet; g.p'., first gill-pouch, cut open to show internal lamellae; g.p.6, sixth gill-pouch; v., ventricle of heart; ao., aorta; a., common exhalant aperture." -Thomson, 1916

Hagfish Respiratory System

"Respiratory system of hag, from ventral surface. b., Barbules; m., mouth opening on ventral surface;…