456 University of California Publications in Zoology [Vol. 22 



He deals with specimens from Trieste and also some from Naples, 

 which he claims differ slightly, but he does not give a specific name for 

 either form. The next important anatomical paper dealing with the 

 digestive organs is that of Sigerfoos (1908), who studied Xylotrya 

 (now Bankia) gouldi Jeffreys with occasional, references to Teredo 

 dilatata Spengler (=T. sigerfoosi Bartsch, 1922) and to Teredo 

 navalis Linn. (= T. beaufortana Bartsch, 1922). In the account of the 

 alimentary tract, only Xylotrya gouldi is discussed. The detailed 

 anatomy of our species seems, then, to have remained undescribed. 

 Comparison with some of the more salient points in the descriptions 

 of the above authors will be made in this paper, but a detailed com- 

 parative account had best await further knowledge of other species. 



Acknowledgments 



This study has been made possible by facilities provided by the 

 San Francisco Bay Marine Piling Committee and is a part of their 

 program of investigation of the marine borers of this region. I 

 am indebted to Professor C. A. Kofoicl for direction and advice 

 throughout the progress of the work. I am also grateful to Professor 

 C. V. Taylor for suggestions and assistance, and to Dr. R. C. Miller, 

 associate biologist of the Piling Committee, for constant cooperation. 



METHODS 



Dissections were made under alcohol with the aid of a binocular 

 dissecting microscope, and were supplemented with cross and sagittal 

 sections. Bouin's, Zenker's, and Gilson's reagents were found to be 

 equally satisfactory for killing and fixing. Being acid, they also 

 decalcified the shell. A mixture of cedar oil and oil of bergamot in 

 which was dissolved some anhydrous carbolic acid (Eycleshymer's 

 clearing fluid) was most satisfactory for dehydrating and de-alcoholiz- 

 ing, following the use of 95 per cent alcohol. It was necessary to 

 infiltrate with paraffin in partial vacuum to get good results. The 

 sections were, as a rule, cut ten microns thick and stained with 

 Delafield's haematoxylin. Iron haematoxylin was also satisfactory. 



Ciliary currents were followed in the living animal by means of 

 small quantities of red mercuric sulphide (vermilion pigment). This 

 material is as fine as carmine, but much heavier, and therefore not 

 liable to float above the cilia. Very fine carborundum dust was used 

 as a substitute for the fine sand recommended by Kellogg (1915). It 

 was fairly satisfactory. 



