Section II. DENTICETE (cf. p. 35).
Denticete, Gray, l. c. pp. 62, 194; Synops. Whales & Dolph. p. 3.
Odontoceti or Delphinoidea, Flower, l. c. p. 111.
Teeth well developed in one or both jaws, sometimes deciduous. Palate without baleen. Head large or moderate, compressed. Tympanic bones two, dissimilar, separate, becoming united, sunk in a cavity in the base of the skull. Gullet large.
The suborders in this section have certain relations to each other by which they may be arranged in two parallel series:—
| A. Nostrils separate, elongated. | B. Nostrils united, transverse. | |
|---|---|---|
| Teeth only in the lower jaw. Cervical vertebræ often united | Physeteroidea. | Ziphioidea. |
| Teeth well developed in both jaws. Jaws beaked | Susuoidea. | Delphinoidea. |
Division I. Nostrils longitudinal, parallel or diverging; each covered with a valve (cf. [p. 62]).
Suborder III. PHYSETEROIDEA.
Physeteroidea, Gray, l. c. p. 195; Synops. Whales & Dolph. p. 3.
Physeteridæ (Physeterinæ), Flower, Tr. Zool. Soc. vol. vi. p. 113.