PLATE VII. 
Fig. 1. Tympanic bone of a large species of Balmnoptera, coated and impregnated with manganese (natural 
size). Station 285 ; 2375 fathoms. South Pacific. 
Fig. 2. Section of bulla of BoUxnoptera (perhaps Balsenoptera antarctica), similar to the preceding (natural 
size). Station 286 ; 2335 fathoms. South Pacific. 
Fig. 3. Bulla of Balsenoptera (perhaps Balsenoptera rostrata), with a considerable coating of manganese (natural 
size). Station 286 ; 2335 fathoms. South Pacific. 
Figs. 4 and 5. Right and left bull® of a whale belonging to the Bal®nid®, upper and under surfaces (natural 
size). The markings shown in fig. 5 were found on both of the bones and are of the same 
character ; these are the only bones taken during the cruise with such marks, and they differ from 
all the other earbones in other respects as well as in the markings. Station 286 ; 2335 fathoms. 
South Pacific. 
Figs. 6 and 7. Tympano-periotic bones of Mesoplodon {Mesoplodon layardi ?), outer and inner surfaces (natural 
size). The bones were coated with manganese and attached when brought up, but in the majority 
of cases the petrous and tympanic bones were separate. Station 276 ; 2350 fathoms. South 
Pacific. 
