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Great Ant-eater as it is usually called (Fig. 9)does not climb trees, though mostly found in forest-districts. These three animals are all widely distributed in the woodlands of tropical America, but never met with elsewhere. The Armadilloes (Dasypodide) are mostly inhabitants of more open districts (see Fig. 10, p. 59). Besides the three living
families of Edentates, there are two (the Megatheriidæ and Glyptodontidæ) now extinct, which are chiefly characteristic of the Neotropical Region, though remains of them have also been found in certain formations in North America (6).
The fourth order of mammals, the Ungulates, is very poorly represented in the Neotropical Region, four only out of the fourteen usually recognised families being found within its limits. The Peccaries (Dicotylide) consist of only two species, of which one (D. tajacu) ranges as far
north as the Southern United States, and the other is confined to the Neotropical Region. A second family, the Camelidæ, is shared by the Neotropical Region with the Old World. The representatives of this family in the New World are the Lamas, belonging to the genus Lama (see Fig. 11). They are entirely confined to the higher ranges of the Andes and to the desolate plains of Patagonia.
The Deer (Cervidx) of the Neotropical Region all belong to two peculiar genera (Cariacus and Pudua), of which the former extends northwards throughout the United States
to British Columbia, while the latter is found only in Western South America
Finally, the Tapirs (Tapiridæ) are represented by four species, all of which are peculiar to this region, the only other existing Tapir known being the Indian Tapir of the of the group
Malay Peninsula. The explanation of this curious case of discontinuous distribution is afforded by the past history
During Miocene and Pliocene times, members of this genus and its allied forms were found both in North America and also throughout the Old World from France to China. This gives us direct evidence of the former much wider extension of the family of Tapirs, and bridges over the present great gap in its distribution.
As already stated, the fauna of the Neotropical Region is almost as remarkable for the absence of certain families as it is for the presence of peculiar forms. This is specially noticeable in the Ungulates. There is no existing representative of the four great families of the Oxen, Rhinoceroses, Horses, and Elephants in this region, though remains of the latter two groups have been found in most recent deposits of Argentina. Here they were probably immigrants from the north, which survived but a short time in this locality.
Turning now to the Rodents, we find that out of the four chief divisions into which this order is separated—the Squirrels (Sciuromorpha), the Mice (Myomorpha), the Porcupines (Hystricomorpha), and the Hares (Duplicidentata)—the first two and the last contain very few peculiar genera and no peculiar families in this Region. But, on the other hand, out of the six families of Hystricomorpha four are restricted to this region, while of the remaining two, one (the Octodontidæ) is found elsewhere only in Africa, and the other, the Porcupines (Hystricidæ) is of wide distribution. Moreover, all the Neotropical genera of the Hystricomorphine division are, without exception, contined to this region.
The Carnivores, which follow next, are well represented in the Neotropical Region, but belong generally to families of wide distribution. But one family, the Raccoons (Procyonidx), with the exception of a single genus (Ælurus), which is perhaps doubtfully referred to it, is entirely confined to the New World. On the other hand, the Viverridæ, so widely spread in the Old World, are entirely absent in America.
With the exception of some four or five species of Shrews, which have obviously spread southwards from the Nearctic Region, wherein they are found in considerable numbers, the Insectivores are represented in the Neotropical Region only by a single remarkable family. This is the Solenodont-a characteristic form of the Greater Antilles -absolutely unknown elsewhere. The Insectivores are usually considered to be the most generalised of all the mammalian orders, and to be the least changed descendants of the ancestral group from which most of the other orders of mammals have originated. If this be the case, it seems strange that we should find no traces of them on the continent of South America, which was, doubtless, long isolated from the rest of the world, and which still contains many representatives of primitive and declining types. The palæontological history of the Insectivores is, however, as yet very incomplete, as very few fossil forms of this order have been described. It is, therefore, possible that when future discoveries have increased our knowledge on this subject, this seeming anomaly may be explained.
The Neotropical Bats (Chiroptera) are of much interest; they are included in three families, of which two (Vespertilionidæ and Emballonuridæ), although containing several peculiar genera, are found in other parts of the