7. _Berardius bairdii._ Centerville, California.

Inner aspect. Nat. size.

[Illustration: Plate 37 PERIOTIC BONES OF MESOPLODON, ZIPHIUS, AND

BERARDIUS]

Right periotic bones of _Mesoplodon_, _Ziphius_, and _Berardius_.

Fig. 1. _Mesoplodon densirostris._ (?) Annisquam, Massachusetts.