GENERAL DISTRIBUTION.--Atlantic, Mediterranean, Indian Ocean, and Southern Ocean. This family consists of the beaked whales, which have no permanent teeth in the upper jaw. The genera, according to Dr. Gray, are, _Hyperoodon_ (2 species) "bottle-nosed whales," North Sea; _Lagenocetus_ (1 species), North Sea; _Epiodon_ (2 species), North and South Atlantic; _Petrorhynchus_ (2 species), Mediterranean Sea and Southern Ocean; _Berardius_ (1 species), New Zealand; _Xiphius_ (1 species) North Atlantic; _Dolichodon_ (1 species), Cape of Good Hope; _Neoziphius_ (1 species) Mediterranean; _Dioplodon_ (1 species), Indian Ocean. FAMILY 40.--MONODONTIDÆ. (1 Genus, 1 Species.) The "Narwhal" (_Monodon monoceros_) which constitutes this family, is placed by Dr. Gray along with the "white whales," in his family Belugidæ. It inhabits the North Sea. FAMILY 41.--DELPHINIDÆ. (24 Genera or Sub-Genera, 100 Species.) GENERAL DISTRIBUTION.--All Oceans, Seas, and Great Rivers of the globe. This family, including the Porpoises, Dolphins, White Whales, &c., may be described as small, fish-shaped whales, having teeth {209}in both jaws. According to Dr. Gray they form seven families and 24 genera; according to Professor Carus, four sub-families and 8 genera, but as these groups appear to be established on quite different principles, and often differ widely from each other, I shall simply enumerate Dr. Gray's genera with their distribution as given in his British Museum Catalogue. _Platanista_ (2 species), long-snouted porpoises, inhabiting the Ganges and Indus; _Inia_ (1 species), a somewhat similar form, inhabiting the upper waters of the Amazonian rivers: _Steno_ (8 species), Indian Ocean, Cape of Good Hope, and West Pacific; _Sotalia_ (1 species), Guiana; _Delphinus_ (10 species), all the oceans; _Clymenia_ (14 species), all the oceans; _Delphinapterus_ (1 species), South Atlantic; _Tursio_ (7 species), Atlantic and Indian Oceans; _Eutropia_ (2 species), Chili, and Cape of Good Hope; _Electra_, (8 species), all the oceans; _Leucopleurus_ (1 species), North Sea; _Lagenorhynchus_ (1 species), North Sea; _Pseudorca_ (2 species), North Sea, Tasmania; _Orcaella_ (2 species), Ganges; _Acanthodelphis_ (1 species), Brazil; _Phocæna_ (2 species), North Sea; _Neomeris_ (1 species), India; _Grampus_ (3 species), North Sea, Mediterranean, Cape of Good Hope; _Globiocephalus_ (14 species), all the oceans; _Sphærocephalus_ (1 species), North Atlantic; _Orca_ (9 species), Northern and Southern Oceans; _Ophysia_ (1 species), North Pacific; _Beluga_ (6 species), Arctic Seas, Australia; _Pontoporia_ (1 species), Monte Video. _Fossil Cetacea._