Archegosaurus is a genus of amphibian which lived during the Asselian to Wuchiapingian ages of the Permian, around 299-253 million years ago.

Archegosaurus Head

Archegosaurus is a genus of amphibian which lived during the Asselian to Wuchiapingian ages of the Permian,…

Archegosaurus is a genus of amphibian which lived during the Asselian to Wuchiapingian ages of the Permian, around 299-253 million years ago. Pictured here is the dorsal vertebrae.

Dorsal Vertebrae of the Archegosaurus

Archegosaurus is a genus of amphibian which lived during the Asselian to Wuchiapingian ages of the Permian,…

"Ten to fiteen inches long, of a brownish or grayish color, spotted with black. On each side of the neck there is a large aperture, within which there are branchial arches: they are also projecting branched gills attached to the opercula or flaps, which close these orifices." — Goodrich, 1859

Axolotl

"Ten to fiteen inches long, of a brownish or grayish color, spotted with black. On each side of the…

In Amphibians the nervous system is but slightly developed. The cerebrum is small; the cerebellum is scarcely visible. Shown is the brain of an alligator. Labels: 1, Olfactory ganglions. 2, Cerebrum. 3, Optic ganglions. 4, Cerebellum. 5, Medulla Oblongata and Spinal Cord.

Brain of an Alligator

In Amphibians the nervous system is but slightly developed. The cerebrum is small; the cerebellum is…

Branchiosaurus (Greek for "gill lizard") is a genus of small, lightly-built early prehistoric amphibians. Pictured here is the dorsal vertebra.

Dorsal Vertebra of Branchiosaurus

Branchiosaurus (Greek for "gill lizard") is a genus of small, lightly-built early prehistoric amphibians.…

"Figure 1 represents the embryo as it appears several days after the egg is deposited." — Goodrich. 1859

Embryo

"Figure 1 represents the embryo as it appears several days after the egg is deposited." — Goodrich.…

"Figure 2 gives an outline of its form; the arrows at the side of the head show the currents of water which are seen to flow to the branchiae by the breathing of the young animal." — Goodrich. 1859

Form of the embryo

"Figure 2 gives an outline of its form; the arrows at the side of the head show the currents of water…

The foot of a frog, which is useful in and out of water.

Frog Foot

The foot of a frog, which is useful in and out of water.

This illustration shows the ancient fossile of an amphibian. Fossils are the mineralized or otherwise preserved remains or traces of animals, plants, and other organisms.

Fossil

This illustration shows the ancient fossile of an amphibian. Fossils are the mineralized or otherwise…

A side view of a frog's internal structure.

Frog

A side view of a frog's internal structure.

A ventral view of a frog's internal structure.

Frog

A ventral view of a frog's internal structure.

A ventral view of a frog's internal nervous system.

Frog

A ventral view of a frog's internal nervous system.

An illustration of a frog sitting on the bank of a pond and scratching his head.

Frog Sitting on Bank and Scratching Head

An illustration of a frog sitting on the bank of a pond and scratching his head.

An illustration of a frog sitting on the bank of a pond looking out into the water.

Frog Sitting on Bank Looking at Pond

An illustration of a frog sitting on the bank of a pond looking out into the water.

The skeleton of a frog.

Frog skeleton

The skeleton of a frog.

Nearing the end of its development, a gradually shrinking tail is all that remains of the tadpole.

Frog with tail

Nearing the end of its development, a gradually shrinking tail is all that remains of the tadpole.

"The common frog of Europe, a common and well-known animal." — Goodrich. 1859

Common frog

"The common frog of Europe, a common and well-known animal." — Goodrich. 1859

The common frog, Rana temporaria.

Common Frog

The common frog, Rana temporaria.

"It is rather larger than the common frog, and its nocturnal croakings are so loud and disagreeable, that temporary dwellers in the neighborhood of ponds frequented by it, are often prevented from sleeping by its clamorous chorus. It is this species that is most approved of on the continent for culinary purposes." — Goodrich, 1859

Edible frog

"It is rather larger than the common frog, and its nocturnal croakings are so loud and disagreeable,…

"The edible frog (Rana esculenta)." -Thomson, 1916

Edible Frog

"The edible frog (Rana esculenta)." -Thomson, 1916

A diagram showing the motions a young frog makes while swimming. In this stage of life, the frog makes ellipses in order to move through the water.

Ellipses of Swimming Frog

A diagram showing the motions a young frog makes while swimming. In this stage of life, the frog makes…

The flying frog is an amphibian "having enormously long webbed toes, enabling it to sustain a kind of flight." -Whitney, 1911

Flying Frog

The flying frog is an amphibian "having enormously long webbed toes, enabling it to sustain a kind of…

A diagram showing the motions a young frog makes whilst swimming. In this stage of the frog's life, the frog uses looping motions to move through the water.

Loops of Swimming Frog

A diagram showing the motions a young frog makes whilst swimming. In this stage of the frog's life,…

"It is one to two feet long, dark slate color, feeds on worms, crawfish, fishes, and aquatic reptiles. It is very voracious, and nothing it can master is spared." — Goodrich, 1859

Alleghany hell-bender

"It is one to two feet long, dark slate color, feeds on worms, crawfish, fishes, and aquatic reptiles.…

African dwarf frogs of genus Hymenochirus, also known as dwarf aquatic frogs, are frogs native to Sub Saharan Africa. Pictured here in the vertebral column.

Vertebral Column of Hymenochirus

African dwarf frogs of genus Hymenochirus, also known as dwarf aquatic frogs, are frogs native to Sub…

"Two feet long, black above and dusky beneath. It is of an eel-like form, lives in the muddy water of the rice swamps, and feeds on worms and insects." — Goodrich, 1859

Siren lacretina

"Two feet long, black above and dusky beneath. It is of an eel-like form, lives in the muddy water of…

The Common Mudpuppy (Necturus maculosus) is a species of aquatic salamander found throughout the northeastern United States, and parts of Canada. Mudpuppies prefer shallow water with many places to hide, but have been found at depths of up to 90 feet. The mating season is late autumn, however eggs are not laid until late spring when 50 to 100 eggs are deposited in a nest cavity under a rock or other object. It takes 1 to 2 months for the eggs to hatch and 4 to 6 years for the young to reach maturity. Mudpuppies may live for up to 20 years.

Common Mudpuppy

The Common Mudpuppy (Necturus maculosus) is a species of aquatic salamander found throughout the northeastern…

Newts belong to the "tailed" amphibian family; Urodela.

Newt

Newts belong to the "tailed" amphibian family; Urodela.

"In the newt a tail is superadded to the extremities, the tail and the extremities both acting in swimming."—Pettigrew, 1874

Crested Newt

"In the newt a tail is superadded to the extremities, the tail and the extremities both acting in swimming."—Pettigrew,…

"It is three and a half inches long, the skin smooth as a frog's; it lives in ponds and ditches, and is devoured in great quantites by fish of various kinds.' — Goodrich, 1859

Smooth newt

"It is three and a half inches long, the skin smooth as a frog's; it lives in ponds and ditches, and…

A pollywog, another phase of tadpole development.

Pollywog

A pollywog, another phase of tadpole development.

The mud puppy has two pairs of legs. It also has persistent external gills. It can attain a length of two feet.

Mud Puppy

The mud puppy has two pairs of legs. It also has persistent external gills. It can attain a length of…

"Salamander is a genus of reptiles closely allied to the frog, from which it differs in having an elongated body terminated by a tail, and four feet of equal length. Together with the frog, this genus is included under the order Batrachia, and is easily distinguished from the lizards by having no nails on the toes, a naked skin destitute of scales, and a heart with a single auricle. "—(Charles Leonard-Stuart, 1911)

Salamander

"Salamander is a genus of reptiles closely allied to the frog, from which it differs in having an elongated…

A class of animals allied to the newts, which closely resemble the lizards. Many species have been described. All have an elongated body, long tail, and four legs.

Salamander

A class of animals allied to the newts, which closely resemble the lizards. Many species have been described.…

A salamander.

Salamander

A salamander.

The name given to various animals included in the class Amphibia and in the order Urodela of that class. The salamanders may be divided into the land salamander and the water salamanders.

Cold Blooded Salamander

The name given to various animals included in the class Amphibia and in the order Urodela of that class.…

"Salamanders have the honor of appearing prominently in fabulous narratives. The Greeks believed that they could live in fire."

Land-Salamander

"Salamanders have the honor of appearing prominently in fabulous narratives. The Greeks believed that…

A woodland salamander with a rusty red back from head to tail.

Red Back Salamander

A woodland salamander with a rusty red back from head to tail.

A black salamander with yellow spots on its back.

Spotted Salamander

A black salamander with yellow spots on its back.

"Is five to seven inches long,; blueish-black, with bright yellow spots; habits nocturnal, living under rocks, stones, and decaying trees, found from Maine to Maryland." — Goodrich, 1859

Violet-colored salamander

"Is five to seven inches long,; blueish-black, with bright yellow spots; habits nocturnal, living under…

"The Land Salamanders, unlike the Tritons, are ovo-viparous, though the young at first inhabit the water and undergo metamorphoses till they arrive at the mature state which fits them for living on land, where they haunt cool and moist places, being not unfrequently found about fallen timber or old walls. Their food primarily consists of insects, worms, and small molluscous animals." — Goodrich, 1859

Salamanders

"The Land Salamanders, unlike the Tritons, are ovo-viparous, though the young at first inhabit the water…

24. Various corals, 25. Razor-shell, 26. Cockle, 27. Various winkels, 28. Shore crab, 29. Father lasher, 30. Periophthalamus, 31. Lobworm, 32. Gunnel

Types of Seashore Life

24. Various corals, 25. Razor-shell, 26. Cockle, 27. Various winkels, 28. Shore crab, 29. Father lasher,…

A developing tadpole.

A developing tadpole

A developing tadpole.

A developing tadpole.

Developing tadpole

A developing tadpole.

A developing tadpole.

Developing tadpole

A developing tadpole.

A tadpole developing, with small rear legs beginning to form.

Developing tadpole

A tadpole developing, with small rear legs beginning to form.

"Figure 5 shows the form of the tadpole when first hatched, which usually takes place about four weeks after depositing the egg." — Goodrich. 1859

Newly hatched tadpole

"Figure 5 shows the form of the tadpole when first hatched, which usually takes place about four weeks…

The development of a toad, image 1.

Toad

The development of a toad, image 1.

The development of a toad, image 3.

Toad

The development of a toad, image 3.

The development of a toad, image 4.

Toad

The development of a toad, image 4.

The development of a toad, image 5.

Toad

The development of a toad, image 5.

A tailless amphibian.

Toad

A tailless amphibian.

"It is a harmless animal, though its ungainly appearance has made it the subject of general aversion." — Goodrich, 1859

Common European toad

"It is a harmless animal, though its ungainly appearance has made it the subject of general aversion."…

"Resembles the common toad of Europe in appearance: there are also other foreign species, among which is the accoucheur toad, which not only assists the female in excluding her eggs, but attaches them afterwards to his own hind-legs, where the young are developed until they arrive at the tadpole state, when he visists the water and the escape. This species is common in the vicinity of Paris." — Goodrich, 1859

Natter-jack toad

"Resembles the common toad of Europe in appearance: there are also other foreign species, among which…

"Is of a brownish or light ash-color, and is found under logs and the bark of decayed trees." — Goodrich, 1859

Squirrel tree-toad

"Is of a brownish or light ash-color, and is found under logs and the bark of decayed trees." —…

"At the breeding season the back of the female exhbits a number of small pits; into these pits the male collects the eggs laid by the female in the edge of the water, and presses them down; they are then covered by a natural operculum, and there they are hatched, in the same manner as the free larvae of the other Batrachians." — Goodrich, 1859

Surinam toad

"At the breeding season the back of the female exhbits a number of small pits; into these pits the male…