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Remarks on the Distribution of the Chdonia.
The four families into which the Chelonia are classed have all of them a wide distribution, though noDe are universaL The Ethiopian region seems to be the richest, as it possesses 3 of the four families, while no other region has more than 2; and it also possesses 7 peculiar genera. Next comes the Neotropical region with 2 families and 6 peculiar genera; the Australian with 3, and the Nearctic with 2 peculiar genera; while the Oriental and Palsearctic regions possess none that are peculiar. There are about 30 genera and 200 species in the whole order.
Fossil Chelonia.—The earliest undoubted remains of this order occur in the Upper Oolite. These belong to the Cheloniidse and Emydidss, which are also found in the Chalk. In the Tertiary beds Chelonia are more abundant, and the Trionychidse now appear. The Testudinidse are first met with in the Miocene formation of Europe and the Eocene of North America, the most remarkable being the gigantic Colossochelys Atlas of the • Siwalik Hills. It appears, therefore, that the families of the order Chelonia were already specialised in the Secondary period, a fact which, together with their more or less aquatic habits, sufficiently accounts for their generally wide distribution. Species of Testudo, Emys, and Trionyx, are found in the Upper Miocene of the south of France.
FAMILY 1.-CÆCILIADÆ. (4 Genera, 10 Species.)
The Cæciliadæ are a curious group of worm-like Amphibia sparingly scattered over the three great tropical regions. The genera are,—Cæcilia, which inhabits West Africa, Malabar and South America; Siphonopsis, peculiar to Brazil and Mexico; Ichthyopsis, from Ceylon and the Khasya Mountains; and Rhinatrema from Cayenne.
FAMILY 2.—SIRENIDÆ. (1 Genus, 3 Species.)
The genus Siren, consisting of eel-like Batrachians with two anterior feet and permanent branchiæ, inhabits the SouthEastern States of North America from Texas to Carolina.
The Proteidas have four feet and persistent external branchiae. The two genera are,—Proteus (1 sp.), found only in caverns of Central Europe; and Menobranchus, which are like newts in form, and inhabit the Eastern States of North America.
Family 4—AMPHIUMULE. (1 Genus, 2 Species.)
The genus Amphiuma, or Murcenopsis, consists of slender eellike creatures with four rudimentary feet, and no external branchiae. The species' inhabit the Southern United States from New Orleans to Carolina
There are large Salamanders of repulsive appearance, found only in Eastern Asia and the Eastern United States. The genera are,—Sieboldia (2 sp.), Japan and north-west China; MeTwpoma — Protonopsis (2 sp.), Ohio and Alleghany rivers.
FAMILY 6.-SALAMANDRIDÆ. (20 Genera, 85 Species.)
PALRARCTIC ETHIOPIAN I ORIENTAL I AUSTRALIAN
The Salamandridæ, of which our common Newts are characteristic examples, form an extensive family highly characteristic of the North Temperate regions, a few species only extending into the Neotropical region along the Andes to near Bogota, and one into the Oriental region in Western China. The genera, as arranged by Dr. Strauch, are as follows :
Salamandra (2 sp.), Central and South Europe and North Africa; Pleurodeles (1 sp.), Spain, Portugal, and Morocco; Bradybates (1 sp.), Spain ; Triton (16 sp.), all Europe except the extreme north, Algeria, North China and Japan, Eastem States of North America, California and Oregon ; Chioglossa (2 sp.) Portugal and South Europe ; Salamandrina (1 sp.), Italy to Dalmatia; Ellipsoglossa (2 sp.), Japan; Isodactylium (2 sp.), East Siberia ; Onychodactylus (1 sp.), Japan ; Amblystoma (21 sp.), Nearctic region from Canada and Oregon to Mexico, most abundant in Eastern States; Ronodon (1 sp.), Tartary and North-east China; Dicamptodon (1 sp.), California ; Plethodon (5 sp.), Massachusetts to Louisiana, and Vancouver's Island to California; Desmognathus (4 sp.), Eastern United States south of latitude 43° ; Anaides (1 sp.), Oregon and Northern California; Hemidactylium (2 sp.), South-eastern United States and Southern California; Heredia (1 sp.), Oregon and California ; Spelerpes (18 sp.), Eastern United States from Massachusetts to Mexico, Guatemala, Costa Rica and Andes of Bogota, with a species in South Europe; Batrachoseps (2 sp.), South-eastern United States and California ; Tylotriton (1 sp.), Yunan in West China.
The Ehinophrynidfe are Toads with imperfect ears and a tongue which is free in front The single species of Rhinophrynns, is a native of Mexico.
Family 8.—PHRYNISCLD^E. (5 Genera, 13 Species.)
The Phryniscidse, or Toads with imperfect ears and tongue fixed in front, are widely distributed over the warmer regions of the earth, but are most abundant in the Neotropical region and Australia, while only single species occur in the Old World. The genera are:—
Phryniscus (7 sp.), from Costa Rica to Chili and Monte Video; Rrachycephalus (1 sp), Brazil; Pseudophryne (3 sp.), Australia and Tasmania; Heniisus (1 sp.), Tropical Africa; Micrhyla (1 sp), Java.
Family 9.—HYL Aplesidje. (1 Genus, 5 Species.)