The Amphisbænidæ, which, in the opinion of Dr. Günther, are all comprised in the genus Amphisbæna, inhabit Spain and Asia Minor, North and Tropical Africa, South America as far as Buenos-Ayres and the West Indian Islands.

Family 29.—LEPIDOSTERNIDÆ. (3 Genera, 6 Species.)

The small family of Lepidosternidæ has nearly the same distribution as the last, indicating a curious relationship between the Tropical parts of Africa and America. Lepidosternon and Cephalopeltis are American genera, while Monotrophis is African.

Family 30.—VARANIDÆ. (3 Genera, 30 Species.)

The Varanidæ, or Water Lizards, are most abundant in the Oriental region, whence they extend into the Austro-Malay Islands as far as New Guinea, and into Australia. Several species are found in Africa. Psammosaurus (1 sp.), is found in North Africa and North-western India; Monitor (18 sp.), has the range of the family; while Hydrosaurus (8 sp.) ranges from Siam to the Philippines, New Guinea, and Australia.

Family 31.—HELODERMIDÆ. (1 Genus, 1 Species.)

The genus Heloderma, which constitutes this family, is found in Mexico.

Family 32.—TEIDÆ. (12 Genera, 74 Species.)

The Teidæ, or Teguexins—a group of Lizards allied to the European Lacertidæ, but with differently formed superciliary scales—are highly characteristic of the Neotropical region, abounding almost everywhere from Patagonia to the Antilles and Mexico, and extending northwards to California on the west and to Pennsylvania on the east. The most extensive genus is Ameiva, containing nearly 60 species and having the range of the entire family; Teius (3 sp.), inhabits Brazil and Mendoza; Callopistes (2 sp.), Chili; Centropyx (3 sp.), Paraguay to Alabama; Dicrodon (Peru); Monoplocus (Western Ecuador); with Acrantus, Acanthopyga, Emminia, Crocodilurus, Custa, and Ada, which each consist of a single species, and all inhabit Tropical America.

Family 33.—LACERTIDÆ. (18 Genera, 80 Species.)

The Lacertidæ, or Land Lizards, are small-sized, terrestrial, non-burrowing lizards, very characteristic of the Palæarctic region, which contains more than half the known species, and of the adjacent parts of the Oriental and Ethiopian regions, but extending also to South Africa, to Java, and even to Australia. The best-defined genera are the following:—

Lacerta (10 sp.), ranging over all Central and South Europe to Poland, and farther north in Russia and Siberia, eastward to Persia, and southward to North and West Africa; Zootoca (8 sp.), has nearly the same range in Europe as the last genus, but has representatives in Madeira, South Africa, and Australia; Tachydromus (7 sp.) is widely scattered in Chinese Asia, Japan, Borneo, and West Africa; Acanthodactylus (10 sp.) is most abundant in North Africa, but has a species in South Africa, and two in Central India; Eremias (18 sp.) is found all over Africa, and also in the Crimea, Persia, Tartary and China; Psammodromus (2 sp.), is confined to Spain, France, and Italy; Ophiops (6 sp.), inhabits India, Persia, and Asia Minor to South Russia. Less strongly marked and perhaps less natural genera are the following:—

Thetia (1 sp.), Algiers; Teira (1 sp.), Madeira; Nucras (4 sp.), Caucasus and South Africa; Notopholis (4 sp.), South Europe and South Africa; Algira (3 sp.), North and South Africa; Scrapteira (1 sp.), Nubia; Aspidorhinus (1 sp.), Caspian district; Messalina (4 sp.), North Africa, Persia, and North-west India Cabrita (1 sp.), Central India; Pachyrhynchus (1 sp.), Benguela.

Family 34.—ZONURIDÆ. (15 Genera, 52 Species.)

The Zonuridæ, or Land Lizards, characterised by a longitudinal fold of skin on each side of the body, have a very remarkable distribution. Their head-quarters is the Ethiopian region, which contains more than half the known genera and species, most of which are found in South Africa and several in Madagascar. Next to Africa the largest number of genera and species are found in Mexico and Central America, with a few in the Antilles, South America, and California, and even as far north as British Columbia. Three of the genera form a distinct sub-group—the Glass Snakes,—the four species composing it being located in North Africa, North America, South-eastern Europe, and the Khasya Hills.

The prominent fact in the distribution of this family is, that the mass of the genera and species form two groups, one in South Africa, the other in Mexico,—countries between which it would be difficult to imagine any means of communication. We have here, probably, an example of a once much more extensive group, widely distributed over the globe, and which has continued to maintain itself only in those districts especially adapted to its peculiar type of organization. This must undoubtedly have been the case with the genus Pseudopus, whose two species now inhabit South-eastern Europe and the Khasya Hills in Assam respectively.

The genera are,—Cordylus, Pseudocordylus, Platysaurus, Cordylosaurus, Pleurostrichus, and Saurophis, confined to South Africa; Zonurus, South and East Africa and Madagascar; Gerrhosaurus, ranges over the whole Ethiopian region; Cicigna is confined to Madagascar; Gerrhonotus (22 sp.), ranges from British Columbia, California, and Texas, to Cuba and South America, but is most abundant in Mexico and Central America; Abronia and Barissia, are two genera of doubtful distinctness, peculiar to Mexico; Ophisaurus (the Glass Snake) is found in the Southern United States as far as Virginia; the allied genus Hyalosaurus in North Africa; and Pseudopus, as above stated, in South-east Europe and the Khasya Hills.

Family 35.—CHALCIDÆ. (3 Genera, 8 Species.)

The Chalcidæ are a small group of Lizards characteristic of Tropical America, one species extending into the United States.

The genera are Chalcis (6 sp.), ranging from Central America to Chili; two other species, which have been placed in distinct genera, inhabit North America and Peru.

Family 36.—ANADIADÆ. (1 Genus, 1 Species.)

The single species of Anadia, constituting this family, inhabits Tropical America.

Family 37.—CHIROCOLIDÆ. (1 Genus, 2 Species.)

The genus Heterodactylus, which constitutes this family, inhabits Brazil.

Family 38.—IPHISADÆ. (1 Genus, 1 Species.)

The single species of Iphisa, has been found only at Para in Equatorial America.

Family 39.—CERCOSAURIDÆ. (1 Genus, 5 Species.)

The genus Cercosaura, is known only from Brazil and Ecuador.

Family 40.—CHAMÆSAURIDÆ. (1 Genus, 1 Species.)

This family, consisting of a single species of the genus Chamæsaura, is confined to South Africa.

Family 41.—GYMNOPTHALMIDÆ . (5 Genera, 14 Species.)

The Gymnopthalmidæ, or Gape-eyed Scinks, so called from their rudimentary eyelids, form a small group, which is widely and somewhat erratically distributed, as will be seen by the following account of the distribution of the genera:—

Lerista (1 sp.) and three other species for which Dr. Gray has established the genera—Morethria (1 sp.), and Menetia (2 sp.), are confined to Australia; Cryptoblepharus (4 sp.), is found in West Australia, Timor, New Guinea, the Fiji Islands, and Mauritius; Ablepharus (4 sp.), inhabits Eastern and South-eastern Europe, Persia, Siberia, West Africa, and the Bonin Islands; and Gymnopthalmus (3 sp.), is found in Brazil and the West Indies.

Family 42.—PYGOPODIDÆ. (2 Genera, 3 Species.)

This small family of two-legged Lizards, comprising the genera Pygopus and Delma, is found only in Australia proper and Tasmania.

Family 43.—APRASIADÆ. (1 Genus, 2 Species.)

The genus Aprasia, constituting this family, is found in West and South Australia.

Family 44.—LIALIDÆ. (1 Genus, 3 Species.)

This family is also confined to Australia, the single genus, Lialis, inhabiting the Western and Northern districts.

Family 45.—SCINCIDÆ. (60 Genera, 300 Species.)

The Scincidæ, or Scinks, are an extensive family of smooth-scaled lizards, frequenting dry and stony places, and almost universally distributed over the globe, being only absent from the cold northern and southern zones. The family itself is a very natural one, and it contains many natural genera; but a large number have been established which probably require careful revision. The following include the more important and the best established groups:—

Scincus (2 sp.), North Africa and Arabia; Hinulia (20 sp.), most of the Australian and Oriental regions; Cyclodina (1 sp.), Hombronia (1 sp.), and Lygosomella (1 sp.), all from New Zealand; Keneuxia (1 sp.), Philippines, Moluccas, and Papuan Islands; Elania (1 sp.) New Guinea; Carlia (2 sp.), North Australia and New Guinea; Mocoa (16 sp.), Australia and New Zealand, with species in Borneo, West Africa, and Central America; Lipinia (3 sp.), Philippine Islands and New Guinea; Lygosoma (12 sp.), Australia, New Caledonia, Pelew and Philippine Islands; Tetradactylus (1 sp.), Hemierges (2 sp.), Chelomeles (2 sp.), Omolepida (1 sp.), Lissolepis (1 sp.), Siaphos (1 sp.), Rhodona (3 sp.) Anomalpus (1 sp.), Soridia (2 sp.), and Ophioscincus (1 sp.) all confined to Australia; Cophoscincus (3 sp.), Philippine Islands, Celebes, and Queensland; Plestiodon (18 sp.), China and Japan, Africa, and America as far north as Pennsylvania and Nebraska; Eumeces (30 sp.), South Palæarctic, Oriental and Australian regions, to New Ireland and North Australia; Mabouya (20 sp.), Oriental region, Austro-Malaya, North Australia, the Neotropical region, and to Lat. 42° 30′ in North America; Amphixestus (1 sp.), Borneo; Hagria (1 sp.), and Chiamela (1 sp.), India; Senira (1 sp.), Philippine Islands; Brachymeles (2 sp.), Philippine Islands and Australia; Ophiodes (1 sp.), Brazil; Anguis (3 sp.), West Palæarctic region and South Africa; Tribolonotus (1 sp.), New Guinea; Tropidophorus (2 sp.), Cochin-China and Philippine Islands; Norbea (2 sp.), Borneo and Australia; Trachydosaurus (1 sp.), Australia; Cyclodus (8 sp.), Australia, Aru Islands, and Ceram; Silubosaurus (2 sp.), Egerina (2 sp.), and Tropidolepisma (6 sp.), all peculiar to Australia; Heteropus (7 sp.), Australia, Austro-Malaya, and Bourbon; Pygomeles (1 sp.), Madagascar; Dasia (1 sp.), Malaya; Euprepes (70 sp.), Ethiopian and Oriental regions, Austro-Malaya, South America (?); Celestus (9 sp.), peculiar to the Antilles, except a species in Costa Rica; Diploglossus (7 sp.), the Neotropical region;—with a number of other genera founded on single species from various parts of the world.

Family 46.—OPHIOMORIDÆ. (2 Genera, 2 Species.)

The snake-like Lizard constituting the genus Ophiomorus, is found in Southern Russia, Greece, and Algeria; while Zygnopsis having four weak limbs, has been recently discovered by Mr. Blanford in South Persia. The family is therefore confined to our Mediterranean sub-region.

Family 47.—SEPIDÆ. (7 Genera, 22 species.)

The Sepidæ, or Sand-Lizards, are a very natural group, almost confined to the Ethiopian region, but extending into the desert country on the borders of the Oriental region, and into the south of the Palæarctic region as far as Palestine, Madeira, Spain, Italy, and even the South of France. The genera are:—

Seps (10 sp.), South Europe, Madeira, Teneriffe, Palestine, North Africa, South Africa and Madagascar; Sphenops (2 sp.), North Africa, Syria, West Africa; Scelotes (3 sp.), Angola to South Africa, Madagascar; Thyrus (1 sp.), Bourbon and Mauritius; Amphiglossus (1 sp.), Madagascar; Sphenocephalus (1 sp.), Afghanistan; and Sepsina (4 sp.), South-west Africa.

Family 48.—ACONTIADÆ. (3 Genera, 7 Species.)

This small family of snake-like Lizards has a very curious distribution, being found in South and West Africa, Madagascar, Ceylon, and Ternate in the Moluccas. Acontias (4 sp.), is found in the four first-named localities; Nessia (2 sp.), is confined to Ceylon; Typhloscincus (1 sp.), to Ternate.

Family 49.—GECKOTIDÆ. (50 Genera, 200 Species.)

The Geckoes, or Wall-Lizards, form an extensive family, of almost universal distribution in the warmer parts of the globe; and they must have some exceptional means of dispersal, since they are found in many of the most remote islands of the great oceans,—as the Galapagos, the Sandwich Islands, Tahiti, New Zealand, the Loo-Choo and the Seychelle Islands, the Nicobar Islands, Mauritius, Ascension, Madeira, and many others. The following are the larger and more important genera:—

Oëdura (3 sp.), Australia; Diplodactylus (8 sp)., Australia, South Africa, and California; Phyllodactylus (8 sp.), widely scattered in Tropical America, California, Madagascar, and Queensland; Hemidactylus (40 sp.), all tropical and warm countries; Peropus (12 sp.), the Oriental region, Papuan Islands, Mauritius, and Brazil; Pentadactylus (7 sp.), Oriental region and Australia; Gecko (12 sp.), Oriental region to New Guinea and North Australia; Gehyra (5 sp.), Australia, New Guinea and Fiji Islands; Tarentola (7 sp.), North Africa, North America, Madeira, Borneo, South Africa; Phelsuma (6 sp.), Madagascar, Bourbon, and Andaman Islands; Pachydactylus (5 sp.), South and West Africa, and Ascension Island; Sphærodactylus (5 sp.), the Neotropical region; Naultinus, (6 sp.), New Zealand; Goniodactylus (5 sp.), Australia, Timor, South America and Algiers; Heteronota (4 sp.), Australia, Fiji Islands, New Guinea and Borneo; Cubina (4 sp.), the Neotropical region; Gymnodactylus (16 sp.), all warm countries except Australia; Phyllurus (3 sp.), Australia; Stenodactylus (4 sp.), North and West Africa, and Rio Grande in North America.

The remaining genera mostly consist of single species, and are pretty equally distributed over the various parts of the world indicated in the preceding list. Madagascar, the Seychelle Islands, Chili, the Sandwich Islands, South Africa, Tahiti, the Philippine Islands, New Caledonia, and Australia—all have peculiar genera, while two new ones have recently been described from Persia.

Family 50.—IGUANIDÆ. (56 Genera, 236 Species.)

The extensive family of the Iguanas is highly characteristic of the Neotropical region, in every part of which the species abound, even as far as nearly 50° South Latitude in Patagonia. They also extend northwards into the warmer parts of the Nearctic region, as far as California, British Columbia, and Kansas on the west, and to 43° North Latitude in the Eastern States. A distinct genus occurs in the Fiji Islands, and one has been described as from Australia, and another from Madagascar, but there is some doubt about these. The most extensive genera are:—

Anolius (84 sp.), found in most parts of Tropical America and north to California; Tropidolepis (15 sp.), which has nearly the same range; Leiocephalus (14 sp.), Antilles, Guayaquil, and Galapagos Islands; Leiolæmus (14 sp.), Peru to Patagonia; Sceloporus (9 sp.), from Brazil to California and British Columbia, and on the east to Florida; Proctotretus (6 sp.), Chili and Patagonia; Phrynosoma (8 sp), New Mexico, California, Oregon and British Columbia, Arkansas and Florida; Iguana (5 sp.), Antilles and South America; Cyclusa (4 sp.), Antilles, Honduras, and Mexico.

Among the host of smaller genera may be noted:—

Brachylophus, found in the Fiji Islands; Trachycephalus and Oreocephalus, peculiar to the Galapagos; Oreodeira, said to be from Australia; Diplolæmus and Phymaturus, found only in Chili and Patagonia; and Callisaurus, Uta, Euphryne, Uma, and Holbrookia, from New Mexico and California. All the other genera are from various parts of Tropical America.

Family 51.—AGAMIDÆ. (42 Genera, 156 Species.)

The extensive family Agamidæ—the Eastern representative of the Iguanas—is highly characteristic of the Oriental region, which possesses about half the known genera and species. Of the remainder, the greater part inhabit the Australian region; others range over the deserts of Central and Western Asia and Northern Africa, as far as Greece and South Russia. One genus extends through Africa to the Cape of Good Hope, and there are three peculiar genera in Madagascar, but the family is very poorly represented in the Ethiopian region. Many of these creatures are adorned with beautifully varied and vivid colours, and the little "dragons" or flying-lizards are among the most interesting forms in the entire order. The larger genera are distributed as follows:—

Draco (18 sp.), the Oriental region, excluding Ceylon; Otocryptis (4 sp.), Ceylon, North India, Malaya; Ceratophora (3 sp.), Ceylon; Gonyocephalus (8 sp.), Papuan Islands, Java, Borneo, Pelew Islands; Dilophyrus (7 sp.), Indo-Malaya and Siam; Japalura (6 sp.), Himalayas, Borneo, Formosa, and Loo Choo Islands; Sitana (2 sp.), Central and South India and Ceylon; Bronchocela (3 sp.), Indo-Malaya, Cambodja, and Celebes; Calotes (12 sp.), Continental India to China, Philippine Islands; Oriocalotes (2 sp.), Himalayas; Acanthosaura (5 sp.), Malacca and Siam; Tiaris (3 sp.), Andaman Islands, Borneo, Philippine and Papuan Islands; Physignathus (3 sp.), Cochin-China and Australia; Uromastix (5 sp.), South Russia, North Africa, Central India; Stellio (5 sp.), Caucasus and Greece to Arabia, High Himalayas and Central India; Trapelus (5 sp.), Tartary, Egypt, and Afghanistan; Phrynocephalus (10 sp.), Tartary and Mongolia, Persia and Afghanistan; Lophura (2 sp.), Amboyna and Pelew Islands; Grammatophorus (14 sp.), Australia and Tasmania; Agama (14 sp.), North Africa to the Punjaub, South Africa. The remaining genera each consist of a single species. Eight are peculiar to Australia, one to the Fiji Islands, one to the Aru Islands, three to Ceylon, five to other parts of the Oriental region, one to Persia, and one to South Russia.

Family 52.—CHAMÆLEONIDÆ. (1 Genus, 30 Species.)

The Chamæleons are an almost exclusively Ethiopian group, only one species, the common Chamæleon, inhabiting North Africa and Western Asia as far as Central India and Ceylon. They abound all over Africa, and peculiar species are found in Madagascar and Bourbon, as well as in the Island of Fernando Po.