3. The same. Ventral aspect.

[Illustration: Plate 24 MANDIBLES AND VERTEBRÆ OF ZIPHIUS CAVIROSTRIS]

Mandibles and vertebræ of _Ziphius cavirostris_.

Fig. 1. (Type of _Z. semijunctus_ (Cope).) Charleston, South Carolina.

Cat. No. 21975, U.S.N.M. ⅕ nat. size.

2. (Type of _Z. grebnitzkii_ Stejneger.) Bering Island. Cat. No. 20993,

U.S.N.M. About ⅕ nat. size.