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world, but the third (Phyllostomatidæ) is entirely confined to this region.
This family, which numbers among its members the true Vampires or blood - sucking bats (Desmodus and Diphylla), is a very considerable one, numbering at least sixty species, distributed among thirty-three genera, which are doubtless still to be supplemented by future discoveries.
Finally, the Neotropical Region possesses two families of Monkeys, the Marmosets (Hapalids) and the Capuchins (Cebida), neither of which is found elsewhere. Moreover, both these groups are distinguished from their Old World allies by very important anatomical characters, which render them absolutely distinct from the Old World monkeys and apes.
As a representative of this latter family we give a figure of the Barrigudo Monkey (Lagothrix humboldti) of Upper Amazonia (Fig. 12, p. 64) of which Mr. Bates has written us an excellent account in his well - known “Naturalist on the Amazons.”
Summarising these statements, we find that the Neotropical Region is characterised by the exclusive possession of no less than ten families of mammals, namely:
and by the presence of about 130 genera, of which about 103 are restricted to its boundaries.
On the other hand, when we compare the fauna of the
i One species, Macrotus californicus, has wandered as far north as California.
Neotropical with that of other regions, the deficiencies or “ lipotypes” are manifestly considerable. For example, the following ten families of mammals, all fairly well
spread over the rest of the world except Australia, are
Simiidæ (Anthropoid apes).
SECTION III.—SUBDIVISION OF THE NEOTROPICAL
The divisions of the Neotropical Region, as based on a consideration of the class of birds (8), are six in number, namely :
1. The Antillean Sub-region, containing the Greater and Lesser Antilles, exclusive of Tobago and Trinidad.
2. The Central-American Sub-region, containing all that part of the whole region that is north of Panama.
3. The Colombian Sub-region, containing Trinidad and the slopes of the Andes, through Venezuela, Colombia, Ecuador, and Peru, into Bolivia.
4. The Amazonian Sub-region, embracing the whole watershed of the Orinoco and Amazons up to the hills, and including the highlands of Guiana.
5. The South Brazilian Sub-region, containing the wood region of South-East Brazil, Paraguay, and the adjoining districts.
6. The Patagonian Sub-region, containing Patagonia, Southern Argentina, and Chili, and running up the west coast of the continent to Guyaquil.
This division, although perfectly good when the distribution of Birds is mainly relied upon, presents considerable difficulties in the case of Mammals, owing chiefly to our ignorance of the limits of the distribution of the greater number of the South American mammals, especially of the smaller forms. There is, however, no doubt that the Antilles or West Indies (excluding Trinidad and the other islands off the coast of Venezuela, which are connected with the mainland by quite shallow water) form
a very well-marked Sub-region, in which the terrestrial mammals, though not very numerous, nearly all belong to peculiar genera.
The higher ranges of the Andes from Ecuador southwards, together with the pampas of Southern Argentina and Patagonia, form another well-marked Sub-region characterised by a number of peculiar genera and species. But the whole remainder of the Neotropical Region from Mexico to Southern Brazil contains, so far as we understand it at present, a more or less homogeneous mammalfauna, of which, however, the northern half possesses a considerable admixture of Nearctic forms, while the southern preserves a more purely indigenous facies. It will, therefore, be quite in accordance with the facts of nature, as well as convenient, to separate the northern portion of this extensive area as the Central American (or Transpanamanic) Sub-region. But as regards the southern portion, until our knowledge of the distribution of South American mammals has made greater progress, it seems best to unite the Colombian, Amazonian, and Brazilian Subregions of the Ornithologists into one combined Sub-region, which may be called the Guiano-Brazilian Sub-region.
We shall thus have, as regards Mammals, four Subregions of the Neotropical Region, as follows (see Map, Plate III., p. 82):
1. The Antillean Sub-region, comprising the whole of the West India Islands except Curaçao, Trinidad, and Tobago.
2. The Central-American Sub-region, comprising the low-lying and southern parts of Mexico and Central America as far as the Isthmus of Panama.
3. The Guiano-Brazilian Sub-region, comprising the greater part of South America from the Isthmus of Panama to the southern limits of the great forest in about lat. 30° S., and from the forest of the eastern slopes of the Andes to the Atlantic, including Trinidad and the other islands off the coast of Venezuela.
4. The Patagonian Sub-region, comprising the higher ranges and western slopes of the Andes from Guyaquil to Tierra del Fuego and the pampas of Argentina and Patagonia.
SECTION IV.—THE ANTILLEAN SUB-REGION
The Mammal-fauna of the Antillean Sub-region is exceedingly poor, so poor, indeed, that it seems almost doubtful whether the islands of which it is composed have ever been directly connected with the mainland of America as at present constituted. To begin with the Rodents, four genera of this order are represented within its limits, and three of these are restricted to the Sub-region. Megalomys (a large rat, over twelve inches in length without the tail) is allied to the Vesper-mice of the American continent, and has been obtained only in the islands of Martinique and St. Lucia, where it is now becoming very rare (10). A more important factor in the Antillean mammal-fauna is Capromys, a genus allied, according to Flower and Lydekker, to the Coypu rat of South America, but also showing some affinities to the Porcupines. There are five or six species of this genus usually recognised, of which two or three are restricted to Cuba, one is peculiar to Jamaica, and one to the Bahamas, while another species has been recently discovered in Swan Island, situated