CHAPTER VIII

THE ORDERS SIRENIA AND CETACEA 212

ORDER SIRENIA 212

_Family_ MANATIDÆ, 215; _Manatus_, 215. _Family_ HALICORIDÆ, 220; _Halicore_, 220. _Family_ RHYTINIDÆ, 221; _Rhytina_, 221. EXTINCT SIRENIANS, 222; _Halitherium_, 222; Other forms, 223. Bibliography, 224.

ORDER CETACEA 225

_Suborder_ MYSTACOCETI 234

_Family_ BALÆNIDÆ, 234; _Balæna_, 236; _Neobalæna_, 241; _Rhachianectes_, 241; _Megaptera_, 241; _Balænoptera_, 242; Extinct genera, 245.

_Suborder_ ARCHÆOCETI 246

_Family_ ZEUGLODONTIDÆ, 246; _Zeuglodon_, 246.

_Suborder_ ODONTOCETI 247

_Family_ PHYSETERIDÆ, 247; _Subfamily_ Physeterinæ, 248; _Physeter_, 248; _Cogia_, 250; Extinct physeteroids, 251; _Subfamily_ Ziphiinæ, 251; _Hyperoödon_, 252; _Ziphius_, 254; _Mesoplodon_, 254; _Berardius_, 256; _Choneziphius_, 257. _Family_ SQUALODONTIDÆ, 257; _Squalodon_, 257. _Family_ PLATANISTIDÆ, 257; _Platanista_, 258; _Inia_, 259; _Pontoporia_, 259; Fossil forms, 259. _Family_ DELPHINIDÆ, 260; _Monodon_, 260; _Delphinapterus_, 262; _Phocæna_, 263; _Cephalorhynchus_, 266; _Orcella_, 267; Orca, 267; _Pseudorca_, 268; _Globicephalus_, 268; _Grampus_, 270; _Feresia_, 270; _Lagenorhynchus_, 270; _Delphinus_, 271; _Tursiops_, 271; _Prodelphinus_, 271; _Steno_, 271; _Sotalia_, 272. Bibliography, 272.