The Oligodontidæ are a small family of Ground Snakes which have been separated from the Calamariida, and, with the exception of a few species, are confined to the Oriental region. The best characterised genera are: Oligodon (12 sp.), India, Ceylon, and Philippines; and, Simotes (24 sp.), India to China and Borneo. In addition to these, Achalinus is founded on a single species from Japan; and Teleolepis consists of three species from North and South America. FAMILY 7.-COLUBRIDÆ, (50 Genera, 270 Species.) GENERAL DISTRIBUTION. NEOTROPICAL NEARCTIC PALEARCTIC ETHIOPIAN ORIENTAL AUSTRALIAN SUB-REGIONS. SUB-REGIONS. SUB-REGIONS. SUB-REGIONS. SUB-REGIONS. SUB-REGIONS. The Colubrine Snakes are universally distributed over the globe, and they reach the extreme northern limits of the order. They are, however, almost absent from Australia, being there represented only by a few species of Tropidonotus and Coronella in the northern and eastern districts. This great family consists of four divisions or sub-families: the Coronellinæ (20 genera, 100 species), the Colubrina (16 genera, 70 species), the Dryadinæ (7 genera, 50 species), and the Natricinæ (7 genera, 50 species). The more important genera of Colubridæ are the following: Ablabes, Coronella, Ptyas, Coluber, and Tropidonotus-all have a very wide distribution, but the two last are absent from South America, although Tropidonotus reaches Guatemala; Tomodon, Xenodon, Liopis, Stenorhina, Erythrolampus, Elapochrus, Callirhinus, Enophrys, and Dromicus-are confined to the Neotropical region; Hypsirhynchus, Cryptodacus, Jaltris, and Coloragia, are confined to the West Indian Islands; Chilomeniscus, Conophis, Pituophis, and Ischeognathus, to North America, the latter going as far south as Guatemala; Compsosoma, Zamenis, Zaocys, Atretium, Xenochrophys, and Herpetoreas, are peculiarly Oriental, but Zamenis extends into South Europe; VOL. II.-25 Lytorhynchus, Rhamnophis, Herpetethiops, and Grayia, are Ethiopian; Rhinechis is peculiar to Europe; Megablabes to Celebes, and Styporhynchus to Gilolo; Cyclophis, is found in the Oriental region, Japan, and North America; Spilotes, in the Nearctic and Neotropical regions; Xenelaphis in the Oriental, Ethiopian, and Palearctic regions; Philodryas, Heterodon, and Herpetodryas in America and Madagascar, the latter genus being also found in China. FAMILY 8.-HOMALOPSIDE. (24 Genera, 50 Species.) The Homalopsidæ, or Fresh-water Snakes, have been separated from the Hydride by Dr. Günther, and they include some groups which have been usually classed with the Natricinæ. They are especially characteristic of the Oriental region, where considerably more than half the genera and species are found; next comes the Neotropical region which has 6 species; while none of the other regions have more than 4 or 5. It is to be observed that the Ethiopian species occur in West Africa only, and mostly constitute peculiar genera, so that in this family the separation of the Ethiopian and Oriental regions is very well marked. The best characterised genera of the family are the following: Cantoria (10 sp.), ranging from Europe to Japan, the Philippines, and Timor, with one species in Guinea; Hypsirhina (6 sp.), Bengal, China, and Borneo; Fordonia (3 sp.), Rangoon to Borneo and Timor; Homalopsis (2 sp,), Cambodja to Java; Cerberus (2 sp.), Ceylon and Siam, the Malay Islands, New Guinea, and North Australia; Herpeton (1 sp.), Siam; Ferania (1 sp.), Bengal to Penang; Pythonopsis (1 sp.), Borneo; Myron (2 sp.), India and North Australia; Homalophis (1 sp.), Borneo; Hipistes (1 sp.), Penang; Xenodermus (1 sp.), Java; Neusterophis and Limnophis, with one species each, are peculiar to West Africa; Helicops (2 sp.), North and South America; Farancia and Dimodes, with one species each, are from New Orleans; and a few others imperfectly known from Tropical America. FAMILY 9.-PSAMMOPHIDE. (5 Genera, 20 Species.) The Psammophidae, or Desert Snakes, are a small group characteristic of the Ethiopian and Oriental regions, but more abundant in the former. The distribution of the genera is as follows: Psammophis (16 sp.), ranges from West Africa to Persia and Calcutta; Calopeltis (1 sp.), North and West Africa; Mimophis (1 sp.), Madagascar; Psammodynastes (2 sp.), Sikhim to Cochin China, Borneo and the Philippine Islands; and Dromophis (1 sp.), Tropical Africa. FAMILY 10.-RACHIODONTIDE. (1 Genus, 2 Species.) The Rachiodontidae are a small and very isolated group of snakes of doubtful affinities. The only genus, Dasypeltis (2 sp.), is confined to West and South Africa. Lytorhynchus, Rhamnophis, Herpetethiops, and Grayia, are Ethiopian; Rhinechis is peculiar to Europe; Megablabes to Celebes, and Styporhynchus to Gilolo; Cyclophis, is found in the Oriental region, Japan, and North America; Spilotes, in the Nearctic and Neotropical regions; Xenelaphis in the Oriental, Ethiopian, and Palearctic regions; Philodryas, Heterodon, and Herpetodryas in America and Madagascar, the latter genus being also found in China. FAMILY 8.-HOMALOPSIDE. (24 Genera, 50 Species.) GENERAL DISTRIBUTION. NEOTROPICAL NEARCTIC PALEAROTIC ETHIOPIAN ORIENTAL AUSTRALIAN SUB-REGIONS. SUB-REGIONS. SUB-REGIONS. SUB-REGIONS. SUB-REGIONS. SUB-REGIONS. The Homalopsidæ, or Fresh-water Snakes, have been separated from the Hydride by Dr. Günther, and they include some groups which have been usually classed with the Natricinæ. They are especially characteristic of the Oriental region, where considerably more than half the genera and species are found; next comes the Neotropical region which has 6 species; while none of the other regions have more than 4 or 5. It is to be observed that the Ethiopian species occur in West Africa only, and mostly constitute peculiar genera, so that in this family the separation of the Ethiopian and Oriental regions is very well marked. The best characterised genera of the family are the following:— Cantoria (10 sp.), ranging from Europe to Japan, the Philippines, and Timor, with one species in Guinea; Hypsirhina (6 sp.), Bengal, China, and Borneo; Fordonia (3 sp.), Rangoon to Borneo and Timor; Homalopsis (2 sp,), Cambodja to Java; Cerberus (2 sp.), Ceylon and Siam, the Malay Islands, New Guinea, and North Australia; Herpeton (1 sp.), Siam; Ferania (1 sp.), Bengal to Penang; Pythonopsis (1 sp.), Borneo; Myron (2 sp.), India and North Australia; Homalophis (1 sp.), Borneo; Hipistes (1 sp.), Penang; Xenodermus (1 sp.), Java; Neusterophis and Limnophis, with one species each, are peculiar to West Africa; Helicops (2 sp.), North and South America; Farancia and Dimodes, with one species each, are from New Orleans; and a few others imperfectly known from Tropical America. FAMILY 9.-PSAMMOPHIDE. (5 Genera, 20 Species.) GENERAL DISTRIBUTION. ORIENTAL AUSTRALIAN NEOTROPICAL NEARCTIC PALBARCTIC ETHIOPIAN 11 1.2.3. 4 1 -3.4 The Psammophidæ, or Desert Snakes, are a small group characteristic of the Ethiopian and Oriental regions, but more abundant in the former. The distribution of the genera is as follows: Psammophis (16 sp.), ranges from West Africa to Persia and Calcutta; Calopeltis (1 sp.), North and West Africa; Mimophis (1 sp.), Madagascar; Psammodynastes (2 sp.), Sikhim to Cochin China, Borneo and the Philippine Islands; and Dromophis (1 sp.), Tropical Africa. FAMILY 10.-RACHIODONTIDE. (1 Genus, 2 Species.) GENERAL DISTRIBUTION. NEOTROPICAL NEARCTIC PALEARCTIC ETHIOPIAN ORIENTAL AUSTRALIAN -2. 3 The Rachiodontidae are a small and very isolated group of snakes of doubtful affinities. The only genus, Dasypeltis (2 sp.), is confined to West and South Africa. |