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other. About this same time (but perhaps not contemporaneously) Madagascar must have been connected with some portion of Southern Africa, and the whole of the country would possess no other Primates but Lemuroidea. After, the Madagascar territory (very much larger than the existing island) had been separated, a connection appears to have been long maintained (probably by a northerly route) between the more equatorial portions of Asia and Africa; till those higher forms had become developed, which were afterwards differentiated into Simia, Presbytes, and Cynopithecus, on the one hand, and into Troglodytes, Colobus, and Cyrwcephalus, on the other. In accordance with the principle of competition so well expounded by Mr. Darwin, we can understand how, in the vast Asiatic and African area north of the Equator, with a great variety of physical conditions and the influence of a host of competing forms of life, higher types were developed than in the less extensive and long-isolated countries south of the Equator. In Madagascar, where these less complex conditions prevailed in a considerable land-area, the lowly organized Lemuroids have diverged into many specialized forms of their own peculiar type; while on the continents they have, to a great extent, become exterminated, or have maintained their existence in a few cases, in islands or in mountain ranges. In Africa the nocturnal and arboreal Galagos are adapted to a special mode of life, in which they probably have few competitors.
How and when the ancestors of the Cebidae and Hapalidae entered the South American continent, it is less easy to conceive. The only rays of light we yet have on the subject are, the supposed affinities of the fossil Ccenopithecns of the Swiss, and the Lemuravidae of the North American Eocene, with both Cebidae and Lemuroids, and the fact that in Miocene or Eocene times a mild climate prevailed up to the Arctic circle. The discovery of an undoubted Lemuroid in the Eocene of Europe, indicates that the great Northern Continent was probably the birthplace of this low type of mammal, and the source whence Africa and Southern Asia were peopled with them, as it was, at a later period, with the higher forms of monkeys and apes.
The Pteropidse, or fruit-eating Bats, sometimes called flyingfoxes, are pretty evenly distributed over the tropical regions of the Old World and Australia. They range over all Africa and the whole of the Oriental Region, and northward, to Amoy in China and to the South of Japan. They are also found in the more fertile parts of Australia and Tasmania, and in the Pacific Islands as far east as the Marianne and Samoa Islands; but not in the Sand.wicii Islands or New Zealand.
The genera of bats are exceedingly numerous, hut they are in a very unsettled state, and the synonymy is exceedingly confused. The details of their distribution cannot therefore be usefully entered into here. The Pteropidae differ so much from all other bats, that they are considered to form a distinct suborder of Chiroptera, and by some naturalists even a distinct order of Mammalia.
No fossil Pteropidse have been discovered.
Family 10.—PHYLLOSTOMID^E. (31 Genera, 60 Species.)
The Phyllostomidse, or simple leaf-nosed Bats, are confined to the Neotropical region, from Mexico and the Antilles to the southern limits of the forest region east of the Andes, and to about lat. 33° S. in Chili. None are found in the Nearctic region, with the exception of one species in California (Macrotus Californicus), closely allied to Mexican and West Indian forms. The celebrated blood-sucking vampyre bats of South America belong to this group. Two genera, Desmodus and Diphylla, form Dr. Peters' family Desmodidse. Mr. Dobson, in his recently published arrangement, divides the family into five groups:— Mormopes, Vampyri, Glossophagae, Stenodermata, and Desmodontes.
Numerous remains of extinct species of this family have been found in the bone-caves of Brazil.
The RhinolophidsB, or Horse-shoe Bats (so-called from a curiously-shaped membranous appendance to the nose), range over all the Ethiopian and Oriental regions, the southern part of the Palaearctic region, Australia and Tasmania. They are most abundant and varied in the Oriental region, where twelve genera are found; while only five inhabit the Australian and Ethiopian regions respectively. Europe has only one genus and four species, mostly found in the southern parts, and none going further north than the latitude of England, where two species occur. Two others are found in Japan, at the opposite extremity of the Palaearctic region;
The genera Nyderis and Megaderma, which range over the Ethiopian and'Oriental regions to the Moluccas, are considered by Dr. Peters to form a distinct family, Megadermidas; and Mr. Dobson in his recent arrangement (published after our first volume was printed) adopts the same family under the name of Nycteridae. The curious Indian genus Rhinopoma, -which, following Dr. J. E. Gray, we have classed in this family, is considered by Mr. Dobson to belong to the Noctilionidse.
Fossil Rhinolophidce.—Remains of a species of Rhinolophus still living in England, have been found in Kent's Cavern, near Torquay.
Family 12.—VESPERTILIONID^E. (18 Genera, 200 Species.)
The small bats constituting the family Vespertilionidae, have no nose-membrane, but an internal earlet or tragus, and often very Large ears. They range over almost the whole globe, being apparently only Limited by the necessity of procuring insect food. In America they are found as far north as Hudson's Bay and the Columbia river; and in Europe they approach, if they do not pass the Arctic circle. Such remote islands as the Azores, Bermudas, Fiji Islands, Sandwich Islands, and New Zealand, all possess species of this group of bats, some of which probably inhabit every island in warm or temperate parts of the globe.
The genus Taphozous, which, in our Tables of Distribution in vol. i. we have included in this family, is placed by Mr. Dobson in his family EmbaLLonuridse, which is equivalent to our next family, Noctilionidse.
Fossil Vespertilionidce.—Several living European bats of this family—Scotopkilus murinus, Plecotus auritus, Vespertilio noctula, and V. pipestrellus—have been found fossil in bone-caves in various parts of Europe.
Extinct species of Vespertilio have occurred in the Lower Miocene at Mayence, in the Upper Miocene of the South of France, and in the Upper Eocene of the Paris basin.
The Noctilionidse, or short-headed Bats, are found in every region, but are very unequally distributed. Their head-quarters is the Neotropical region, where most of the genera occur, and where they range from Mexico to Buenos Ayres and Chili, while in North America there is only one species in California. They are unknown in Australia; but one species occurs in New Zealand, and another in Norfolk Island. Several species of Dysopes (or Molossus) inhabit the Oriental region; one or two species being widely distributed over the continent, while two others inhabit the Indo-Malayan Islands. A species of this same genus occurs in South Africa, and another in Madagascar and in the Island of Bourbon; while one inhabits Southern Europe and North Africa, and another is found at Amoy in China. It will be seen therefore, that these are really South American bats, which have a few allies widely scattered over the various regions of the globe. Their affinities are, according to Mr. Tomes, with the Phyllostomidae, a purely South American family. The species which forms the connecting link is the Mystacina tuberculoid, a New Zealand bat, which may, with almost equal propriety be placed in either family, and which affords an interesting illustration of the many points of resemblance between the Australian and Neotropical regions.
Dr. Peters has separated this family into three,—Mormopidse, which is wholly Neotropical, and is especially abundant in the West Indian Islands; Molossidze, chiefly consisting of the genus Molossus; and Noctilionidae, comprising the remainder of the family, and wholly Neotropical. Mr. Dobson, however, classes the Mormopes with the Phyllostomidse, and reduces the