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DEDUCTIONS

1. The Order Ungulata contains about 306 known species, arranged in seventy-one genera and thirteen families.

2. Ungulates are found all over the earth except in the Australian Region. In the Malagasy Sub-region there is but one species, which may possibly be a recent introduction.

3. Ungulates are most abundant in the Ethiopian Region, where 156 species occur. Of the great family Bovida 138 out of 200 known species are restricted to this Region.

4. There are no Bovine Ungulates in the Neotropical Region, and only five (all nearly allied to recent or extinct Palæarctic forms) in the Nearctic Region.

5. In the Neotropical Region there are representatives of only four out of the thirteen families of UngulatesTapirs, Deer, Camels, and Peccaries.

6. There are no Deer (Cervidæ) in the Ethiopian Region.

7. The New World has only 38 species of Ungulates against 270 found in the Old World.

CHAPTER XIII

DISTRIBUTION OF THE CETACEANS AND

SIRENIANS

In a previous chapter on this subject (Chapter VIII., p. 197) I have already stated the principal facts known respecting the distribution of these two marine orders of mammals and need not now repeat them. But I append a list of the genera with the approximate numbers of the generally recognized species and some general indications of their ranges, and I add some general deductions.

Table of the genera of the Order Cetacea, showing the approximate number of valid species and their distribution.

Number of
Species.

SUB-ORDER
MYSTACOCETI.

FAMILY I.
BALÆNIDÆ.

GENERAL DISTRIBUTION. 1. Balæna ..... | 2 Arctic, Temperate and Antarctic

Seas. 2. Neobalæna . . . . Antarctic. 3. Rhachianectes.. North Pacific. 4. Megaptera .... | Atlantic and Pacific, North and

South. 5. Balænoptera. ...| 4 | Widely distributed.

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Number of
Species.

SUB-ORDER ODONTOCETI.

FAMILY II. PHYSETERIDÆ.

Sub-family I.

PHYSETERINÆ. 1. Physeter . . . . | 1 | Tropical and Sub-tropical Seas. 2. Cogia . . . . . . 1 Widely distributed.

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FAMILY III. PLATANISTIDÆ. 1. Platanista .... | 1 | Rivers Ganges, Brahmaputra, and

Indus. 2. Inia . .

| 1 | Upper Amazon. 3. Pontoporia . . . . Estuary of La Plata.

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Sub-family I.

DELPHININÆ. 1. Sotalia. .....

NO DO A OTRO

2. Steno . . . . . 3. Tursiops . . . 4. Delphinus .. 5. Prodelphinus. 6. Tursio. . . . 7. Lagenorhynchus . 8. Sagmatias ... : 9. Teresa . . . . 10. Cephalorhynchus . . 11. Neomeris . . . . 12. Phocæna . . . . . 13. Orcella . . . .

GENERAL DISTRIBUTION. China, Indian Ocean, South

America (partially fluviatile) Indian Ocean and South Atlantic. Widely diffused. Widely diffused. Widely diffused. Antarctic and Pacific Ocean. Widely diffused. Unknown. | Antarctic Ocean. | South Seas.

Indian Ocean. | Atlantic and Pacific Ocean. Indian Ocean and Trawnddy

River.
| Atlantic and Pacific.
Widely diffused.
Widely diffused.
Widely diffused.

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DEDUCTIONS

1. The Order Cetacea contains from eighty to ninety known species, belonging to about forty-four genera and four families.

2. Cetaceans are found in all seas from the Equator to within the Arctic and Antarctic Circles, and in some of the larger rivers (the Ganges, Brahmaputra, Indus, and Irawadi in the Old World, and the Amazon and La Plata in the New).

3. The species of Oceanic Cetaceans are mostly very widely distributed, especially the Delphinidæ, but in some cases are local, some species being confined to the Arctic and Antarctic Seas respectively, and some being peculiar to the Pacific and to the North Atlantic.

4. The Fluviatile Dolphins proper constitute a family of themselves (Platanistide) with a very singular distribution, one genus being restricted to the rivers of India, and two others to those of South America.

5. Besides the Platanistidæ some of the Delphinidæ are found in rivers, such as Orcella fluminalis in the Irawadi, and Sotalia tucuxi (with perhaps others of the same genus) in the Amazon.

6. None of the great lakes of any continent is known to be inhabited by Cetaceans.

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