168 ALLAN HANCOCK PACIFIC EXPEDITION'S VOL. 25 



PLATE 15 



Habitat of Boccardta uncata Berkeley in Newport Bay, California 

 (Sta. 4907), forming muddy tubes clustered between oyster shells, 

 Ostrea lurida Carpenter, partly covered with a small barnacle, Clilha- 

 malus fissus Darwin, exposed at normal low tide, x 12.6. 



