EXPLANATION OF THE LETTERING. 



a. Anus. 



a. c. Alimentary canal. 



at. Atrial aperture. 



It. d. Biliary duct. 



l\ Branchial aperture. 



en. Endostyle. 



7i. Heart. 



/. Liver. 



?/i o. Mouth. 



od. Oviduct. 



tf. (Esophagus. 



r. Reproductive organs. 



s. Stomach. 



ts. Testis. 



v. Ovary. 



v. d. Vas deferens. 



