PLATE XXVI. 



Illustrating paper by F. E. Lloyd, on "The Mechanisms in certain boring 

 Lamellibranch Molluscs." Pp. 307-316. 



(For explanations of letters see page facing Plate XXV.) 



Fig. 4. PholadUlea penita. Interior of left valve of working form. 



Fig. 5. Zirphsea crispata. Interior of left valve. 



Fig. 6. Teredo (sp. unci ). Interior of left valve. The areas^vrithin the 

 ■dotted lines are the places of attachment of adductor muscles. 



Fig. 7. Exterior of right valve of same. 



