MORPHOLOGY OF THE DIGESTIVE TRACT OP 

 TEREDO NAVALIS 



BY 



EDGAR LOCKE LAZIER 



CONTENTS PAGE 



Introduction 455 



Acknowledgments . . 456 



Methods 456 



Morphology of the digestive tract 457 



The digestion of wood 466 



Summary ........... 467 



Literature cited 168 



Explanation of plates ............... 470 



INTRODUCTION 



Notwithstanding' the considerable volume of literature on the 

 Teredinidae which has appeared in the past 200 years, there is to be 

 found no comprehensive and detailed account of the digestive tract. 

 The present paper is an attempt to describe fully the gross anatomy 

 of the entire digestive system of one species as a foundation for future 

 histological and physiological studies and for comparison with other 

 forms. 



The species treated is Teredo navalis Linn. (= T. beachi Bartsch, 

 1921) as identified by Kofoid (1921) and by Kofoid and Miller 

 (1922). The shells and pallets of the same species have been described 

 at some length by Miller (1922 and 1923). Specimens used for the 

 present study were collected from various points in San Francisco Bay. 



Teredo has been the subject of many writings since 1733 when 

 Sellius published the first extensive account of it. In all these there 

 are but few detailed anatomical accounts. Deshayes (1845-1848) is 

 a striking exception, but his figures, excellent as they are, are difficult 

 to interpret. As in most accounts, the identification of the species 

 described is in doubt. Deshayes calls his form Teredo navalis Linn., 

 but this is doubtless incorrect. Quatrefages (1849) gives a brief 

 anatomical account of a species which he names T. fatalis. It is very 

 similar to Deshayes' Teredo, but he differentiates the two on features 

 of the shell, siphons, and ovary. He calls the latter species T. deshayii. 

 Beuk's paper (1899) is concerned chiefly with the excretory organs, 

 but he describes the digestive tract briefly and gives figures of it. 



