3. The same specimen. Humerus. 1/7 nat. size.

4. _Berardius bairdii._ St. George Island, Alaska. Left pectoral limb.

Cat. No. 49727. Male, immature. ⅕ nat. size.

[Illustration: Plate 34 TYMPANIC BONES OF MESOPLODON, ZIPHIUS, AND

BERARDIUS]

Tympanic bones of _Mesoplodon_, _Ziphius_, and _Berardius_.

Fig. 1. _Mesoplodon densirostris_ (?). Annisquam, Massachusetts.