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Family 130.—PALAPTEKYGLILE. (2 Genera, 4 Species.)
Palapteryx (2 sp.); Euryapteryx (2 sp.).
These had a well-developed hind toe, and rudimentary wings.
Family 131.—^PYOENITHID^. (1 Genus, 3 Species.)
A gigantic Struthious bird (JZpyomis), belonging to a distinct family, inhabited Madagascar.
It was first made known by its enormous eggs, eight times the bulk of those of the ostrich, which were found in a subfossil condition. Considerable portions of skeletons have since been discovered, showing that these huge birds formed an altogether peculiar family of the order.
General Remarks on the Distribution of the Struthiones.
With the exception of the Ostrich, which has spread northward into the Palasarctic region, the Struthious birds, living and extinct, are confined to the Southern hemisphere, each continent having its peculiar forms. It is a remarkable fact that the two most nearly allied genera, Struthio and Rhea, should be found in Africa and South Temperate America respectively. Equally remarkable is the development of these large forms of wingless birds in Australia and the adjacent islands, and especially in New Zealand, where we have evidence which renders it probable that about 20 species recently coexisted. This points to the conclusion that New Zealand must, not long since, have formed a much more extensive land, and that the diminution of its area by subsidence has been one of the causes—and perhaps the main one—in bringing about the extinction of many of the larger species of these wingless birds.
The wide distribution of the Struthiones may, as we have already suggested (Vol. I., p. 287.), be best explained, by supposing them to represent a very ancient type of bird, developed at a time when the more specialized carnivorous mammalia had not come into existence, and preserved only in those areas which were long free from the incursions of such dangerous enemies. The discovery of Struthious remains in Europe in the Lower Eocene only, supports this view; for at this time carnivora were few and of generalized type, and had probahly not acquired sufficient speed and activity to enable them to exterminate powerful and quick-running terrestrial birds. It is, however, at a much more remote epoch that we may expect to find the remains of the earlier forms of this group; while these Eocene birds may perhaps represent that ancestral wide-spread type which, when isolated in remoter continents and islands, became modified into the American and African ostriches, the Emeus and Cassowaries of Australia, the Dinornis and dSpyornis of New Zealand.
THE DISTRIBUTION OF THE FAMILIES AND GENEKA OF REPTILES
Family 1.—TYPHLOPID^E.—(4 Genera, 70 Species.)
The Typhlopidae, or Blind Burrowing Snakes, are widely scattered over the warmer regions of the earth, but are most abundant in the Oriental and Australian regions, and least so in the Neotropical. They are absent from the Nearctic region; and in the Palaearctic are found only in South-eastern Europe and Japan.
The most extensive genus is Typhlops, comprising over 60 species, and having a range almost as extensive as the entire family. The other well characterised genera are :—
TypMina (1 sp.), ranging from Penang to Java and Hong Kong; Typkline (1 sp.), the Cape of Good Hope; Dibamus (1 sp.), New Guinea.
The Tortricidse, or Short-tailed Burrowing Snakes, are a small family, one portion of which ranges from India to Cambodja, and through the Malay islands as far as Celebes and Timor; these form the genus Cylindrophis. Another portion inhabits America, and consists of:—
Charina (1 sp.), found in California and British Columbia; and Tortrix (1 sp.), in Tropical America.
We have here a case of discontinuous distribution, indicating, either very imperfect knowledge of the group, or that it is the remnant of a once extensive family, on the road to extinction.
Family 3.—XENOPELTID^E. (1 Genus, 1 Species.)
The curious nocturnal carnivorous Snake, forming the genus Xenopeltis, and the sole representative of this family, ranges from Penang to Cambodja, and through the Malay Islands to Celebes.
The Uropeltidae, or Eough-tailed Burrowing Snakes, are strictly confined to Ceylon and the adjacent parts of Southern India, and would almost alone serve to mark out our second Oriental sub-region. The genera are :—
Rhinophis (7 sp.), Ceylon; Uropdtis (1 sp.), Ceylon; Silybura (8 sp.), Ananially Hills and Neilgherries; Pleciurus (3 sp.), Neilgherries and Madras; and Melanophidium (1 sp.), the Wynand.
Family 5.—CALAMAFJID^E. (32 Genera, 75 Species.)
The Calamariidse, or Dwarf Ground Snakes, are found in all warm parts of the globe, extending north into the United States as far as British Columbia and Lake Superior; but they are absent from the Palaearctic region, with the exception of a species found in Persia. The species are in a very confused state. The best characterised genera are the following:—
Calamaria (20 sp.), Persia, India to Java and the Philippine Islands, Celebes, and New Guinea; Rhabdosoma (18 sp.), Mexico and South America, and also the Malay Islands as far east as Amboyna, Timor, and New Guinea; Typhlocalamus (1 sp.), Borneo; Macrocalamus (1 sp.), India; Aspidura (3 sp.), India and Ceylon; Haplocerus (1 sp.), Ceylon; Streptophorus (3 sp.), Central and South America;—with a host of others of less importance or ill-defined.
Family 6.—OLIGODONTID^E. (4 Genera, 40 Species.)
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