Family 68.—CAVIIDÆ. (6 Genera, 28 Species.)
| General Distribution. | |||||
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| Neotropical Sub-regions. | Nearctic Sub-regions. | Palæarctic Sub-regions. | Ethiopian Sub-regions. | Oriental Sub-regions. | Australian Sub-regions. |
| 1. 2. 3. 4 | — — — — | — — — — | — — — — | — — — — | — — — — |
The Cavies and Agoutis were placed in distinct families by Mr. Waterhouse, in which he is followed by Professor Carus, but they have been united by Professor Lilljeborg, and without pretending to decide which classification is the more correct I follow the latter, because there is a striking external resemblance between the two groups, and they have an identical distribution in the Neotropical region, and with one exception are all found east of the Andes. Dasyprocta (9 sp.), the agouti, ranges from Mexico to Paraguay, one species inhabiting the small West Indian islands of St. Vincent, Lucia, and Grenada; Cælogenys (2 sp.), the paca, is found from Guatemala to Paraguay, and a second species (somewhat doubtful) in Eastern Peru; Hydrochœrus (1 sp.), the capybara inhabits the banks of rivers from Guayana to La Plata; Cavia (9 sp.), the guinea-pigs, Brazil to the Straits of Magellan, and one species west of the Andes at Yça Peru; Kerodon (6 sp.), Brazil and Peru to Magellan; Dolichotis (1 sp,), the Patagonian cavy, from Mendoza to 48° 30′ south latitude, on sterile plains.
Extinct Caviidæ.—Hydrochœrus, Cælogenys, Dasyprocta, and Kerodon, have occurred abundantly in the caves of Brazil, and the last-named genus in the Pliocene of La Plata. Hydrochœrus has been found in the Post-Pliocene deposits of South Carolina. Cavia and Dasyprocta are said to have been found in the Miocene of Switzerland and France. No well-marked extinct genera of this family have been recorded.
If the determination of the above-mentioned fossil species of Cavia and Dasyprocta are correct, it would show that this now exclusively South American family is really derived from Europe, where it has long been extinct.
Family 69.—LAGOMYIDÆ. (1 Genus, 11 Species.)
| General Distribution. | |||||
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| Neotropical Sub-regions. | Nearctic Sub-regions. | Palæarctic Sub-regions. | Ethiopian Sub-regions. | Oriental Sub-regions. | Australian Sub-regions. |
| — — — — | — 2 — 4 | — — 3 — | — — — — | — — — — | — — — — |
The Lagomyidæ, or pikas, are small alpine and desert animals which range from the south of the Ural Mountains to Cashmere and the Himalayas, at heights of 11,000 to 14,000 feet, and northward to the Polar regions and the north-eastern extremity of Siberia. They just enter the eastern extremity of Europe as far as the Volga, but with this exception, seem strictly limited to the third Palæarctic sub-region. In America they are confined to the Rocky Mountains from about 42° to 60° north latitude.
Extinct Lagomyidæ.—Extinct species of Lagomys have occurred in the southern parts of Europe, from the Post-Pliocene to the Miocene formations. Titanomys, an extinct genus, is found in the Miocene of France and Germany.
Family 70.—LEPORIDÆ. (1 Genus, 35-40 Species.)