The Frogs Who Wanted a King. The log thrown down by Jupitor in answer to the frogs' request for a king.

Aesop's Fables

The Frogs Who Wanted a King. The log thrown down by Jupitor in answer to the frogs' request for a king.

The Frogs Who Wanted a King. The stork sent by Jupitor in answer to the frogs' request for a king.

Aesop's Fables

The Frogs Who Wanted a King. The stork sent by Jupitor in answer to the frogs' request for a king.

"The fishing frog is three to five feet long. It has an enormous mouth, armed with numerous pointed teeth. It is exceedingly voracious, and has been known to seize a cod just as it was being drawn out of the water by a hook, and only let go its hold on receiving a severe blow upon the head." — Goodrich, 1859

Angler

"The fishing frog is three to five feet long. It has an enormous mouth, armed with numerous pointed…

An illustration of a bird and frog.

Bird & Frog

An illustration of a bird and frog.

"Showing how the circulation of blood in the web of a frog's foot looks as seen under the microscope." — Blaisedell, 1904

Circulation of blood

"Showing how the circulation of blood in the web of a frog's foot looks as seen under the microscope."…

"Agua-Toad (Bufo marinus), a very large and common South American toad, with enormous parotid glands."-Whitney, 1902

Bufo Toad

"Agua-Toad (Bufo marinus), a very large and common South American toad, with enormous parotid glands."-Whitney,…

Capillaries (C) in the web of the frog's foot connecting a small artery (A) with a small vein (V).

Capillaries in Frog's Foot

Capillaries (C) in the web of the frog's foot connecting a small artery (A) with a small vein (V).

A small portion of the capillary network as seen in the frog's web when magnified about 25 diameters. Labels: a, a small artery feeding the capillaries; v, v, small veins carrying blood back from the latter.

Capillary Network

A small portion of the capillary network as seen in the frog's web when magnified about 25 diameters.…

Cat playing with a frog.

Cat and Frog

Cat playing with a frog.

Cat playing with a frog.

Cat and Frog

Cat playing with a frog.

Cat playing with a frog.

Cat and Frog

Cat playing with a frog.

Cat playing with a frog.

Cat and Frog

Cat playing with a frog.

Circulation in the web of a Frog's foot.

Circulation in the Web of a Frog's Foot

Circulation in the web of a Frog's foot.

A diagram of the circulation of a frog. Labels: 1, The pericardium. 2, The single ventricle. 3, The right auricle. 4, The left auricle. The arrows indicate the direction of the blood.

Circulation of a Frog

A diagram of the circulation of a frog. Labels: 1, The pericardium. 2, The single ventricle. 3, The…

A mother frog bringing her baby frog to see the crawfish doctor.

Crawfish Doctor

A mother frog bringing her baby frog to see the crawfish doctor.

An amphibian with a toothed upper jaw and subcylindric or little dilated sacral diapopyses.

Cystignathidae

An amphibian with a toothed upper jaw and subcylindric or little dilated sacral diapopyses.

"Frog with the left side cut away and some of the organs pulled downward. a, aorta leading from the ventricle; b, bladder; c, spinal cord surrounded by the vertebral column of bone; d, small intestine; e, opening of the lungs into the pharynx; h, ventricle of the heart; k, kidney; l, lung; liv, liver; n, brain; ov, ovary; ovd, oviduct; p, pancreas; r, rectum; sp, spleen; st, stomach; t, tongue; si, small intestine; u, left auricle; ur, ureter; v, vena cava; vc, body of vertebra." —Davison, 1906

Dissected Frog

"Frog with the left side cut away and some of the organs pulled downward. a, aorta leading from the…

Ducklings looking at a frog

Ducklings

Ducklings looking at a frog

A line of toad eggs

Toad Eggs

A line of toad eggs

"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…

"A, columnar cells of intestine; B, polyhedral cells of the conjuctiva; C, ciliated conical cells of the trachea; D, ciliated cell of frog's mothl E, inverted conical cell of the trachea; F, squamous cell of the cavity of the mouth, seen on its broad surface; G, squamous cell, seen edgeways." — Blaisedell, 1904

Various kinds of epithelial cells

"A, columnar cells of intestine; B, polyhedral cells of the conjuctiva; C, ciliated conical cells of…

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.

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.

Frogs are found all over the world, except Antarctica.

Frog

Frogs are found all over the world, except Antarctica.

Frog

Frog

Frog

The heart and lungs of a frog. 1: Heart. 2: Arch of the aorta. 3: Pulmonary artery. 4: Pulmonary veins. 5: Aorta. 6: Vena cava.

Frog

The heart and lungs of a frog. 1: Heart. 2: Arch of the aorta. 3: Pulmonary artery. 4: Pulmonary veins.…

"The Tadpole is the larva of the anurous amphibia, sometimes so far extended as to include larvaæ of the urodela, which undergo a much less complete metamorphosis. At first the young have no respiratory organs or limbs. They are all head and tail with simple entire gills which soon disappear, to be followed by others of more complicated structure, situated within the cavity of the body as in fishes. After a certain length of time the hind legs begin to appear, the head becomes more developed, and the body assumes a more compact form. Still later the forelegs are found to exist fully formed beneath the skin and ready ultimately to burst forth. The tadpole at first seems to derive its subsistence from the fluid absorbed within its body and on the surface, but soon begins to seek its food amidst softened or decomposing vegetable matter. From that period the tadpole begins to assume more and more the appearance of a frog. Toes appear on its hind legs, the tail very rapidly disappears by absorption, and finally the fore-legs become fully developed and the metamorphosis of the tadpole is completed."—(Charles Leonard-Stuart, 1911)

Frog Egg

"The Tadpole is the larva of the anurous amphibia, sometimes so far extended as to include larvaæ…

"The Tadpole is the larva of the anurous amphibia, sometimes so far extended as to include larvaæ of the urodela, which undergo a much less complete metamorphosis. At first the young have no respiratory organs or limbs. They are all head and tail with simple entire gills which soon disappear, to be followed by others of more complicated structure, situated within the cavity of the body as in fishes. After a certain length of time the hind legs begin to appear, the head becomes more developed, and the body assumes a more compact form. Still later the forelegs are found to exist fully formed beneath the skin and ready ultimately to burst forth. The tadpole at first seems to derive its subsistence from the fluid absorbed within its body and on the surface, but soon begins to seek its food amidst softened or decomposing vegetable matter. From that period the tadpole begins to assume more and more the appearance of a frog. Toes appear on its hind legs, the tail very rapidly disappears by absorption, and finally the fore-legs become fully developed and the metamorphosis of the tadpole is completed."—(Charles Leonard-Stuart, 1911)

Frog Eggs

"The Tadpole is the larva of the anurous amphibia, sometimes so far extended as to include larvaæ…

"Galvani found that whenever the nerves of a frog's leg were touched by one metal and the muscles by another, convulsions took place on bringing the two different metals in contact." —Wells, 1857

Frog Experiment

"Galvani found that whenever the nerves of a frog's leg were touched by one metal and the muscles by…

An illustration of a frog ice skating on a lake wearing a hat and jacket.

Frog Ice Skating on Lake

An illustration of a frog ice skating on a lake wearing a hat and jacket.

This illustration shows the leg of a frog.
P. Pelvis, FE. Femur, TI. Tibia, FI. Fibula, TA. Tarsus, MT. Metatarsus, PH. Phalanges, OC. Os Calcis.

Leg of Frog

This illustration shows the leg of a frog. P. Pelvis, FE. Femur, TI. Tibia, FI. Fibula, TA. Tarsus,…

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.

A frog telling the smaller animals a story, while a porcupine eyes some fruit.

Frog Storyteller

A frog telling the smaller animals a story, while a porcupine eyes some fruit.

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 circulation of the blood in the web of a frog's foot. A, an artery; B, capillaries crowded with disks, owing to a rupture just above, where the disks are jammed into an adjacent mesh; C, a deeper vein; the black spots are pigments cells.

Circulation of Blood in a Frog's Foot

The circulation of the blood in the web of a frog's foot. A, an artery; B, capillaries crowded with…

"At their birth they respire by means of gills, and consequently resemble fishes. As they progress in age, they undergo permanent metamorphoses - they acquire lungs and thenceforth an aerial respiration."

Alphabet Frog (Ceratophrys Boiei)

"At their birth they respire by means of gills, and consequently resemble fishes. As they progress in…

"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

"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,…

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 green-tree frog is distinguished by suckers under its toes which enables him to cling to any tree surface.

Green-tree frog

The green-tree frog is distinguished by suckers under its toes which enables him to cling to any tree…

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,…

A diagram demonstrating the motion a frog makes whilst swimming. In this stage of the frog's life, the frog makes waved lines while moving through the water.

Swim Lines of Frog

A diagram demonstrating the motion a frog makes whilst swimming. In this stage of the frog's life, the…

Native to India, the gavial has an very narrow snout, used for hunting fish and frogs.

Gavial

Native to India, the gavial has an very narrow snout, used for hunting fish and frogs.

Chnemu creator-god, married to Hekt, a frog goddess.

Egyptian God, Chnemu

Chnemu creator-god, married to Hekt, a frog goddess.

The heart of a frog (Rana esculenta) from the front. Labels: V, ventricle, Ad, right auricle; As, left auricle; B, bulbus arteriosus, dividing into right and left aorta.

Heart of a Frog

The heart of a frog (Rana esculenta) from the front. Labels: V, ventricle, Ad, right auricle; As, left…

This illustration shows a human leg (front view), and comparative diagrams showing modifications of the leg:
1. Human, 2. Ox, 3. Horse, 4. Bird, 5. Frog, 6. Crocodile, 7. Seal, 8. Dog, 9. Bear
P. Pelvis, FE. Femur, TI. Tibia, FI. Fibula, TA. Tarsus, MT. Metatarsus, PH. Phalanges, OC. Os Calcis.

Human Leg (Front View), and Comparative Diagrams showing Modifications of the Leg

This illustration shows a human leg (front view), and comparative diagrams showing modifications of…

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…

Small branch of a muscular nerve of the frog, near its termination, showing division of the fibers. Labels: a, into two; b, into three.

Muscular Nerve Showing Division of Fiber

Small branch of a muscular nerve of the frog, near its termination, showing division of the fibers.…

Ramifications of nerves and termination in muscular coat of a small artery of the frog.

Nerves in the Artery of a Frog

Ramifications of nerves and termination in muscular coat of a small artery of the frog.

"A genus of anurous amphibians, or tailless batrachians, of the family Discoglossidæ, sometimes made the type of a family Alytidæ."-Whitney, 1902

Nurse Frog

"A genus of anurous amphibians, or tailless batrachians, of the family Discoglossidæ, sometimes…

Frogs and snails

Pictorial divider

Frogs and snails

Indian pipe in the shape of a frog, used for smoking tobacco.

Frog-shaped Indian Pipe

Indian pipe in the shape of a frog, used for smoking tobacco.

A pollywog, another phase of tadpole development.

Pollywog

A pollywog, another phase of tadpole development.

A frame surrounded by various reptiles.

Reptiles

A frame surrounded by various reptiles.

Two mice rowing away from a group of skinny-dipping frogs.

Skinny-dipping Frogs

Two mice rowing away from a group of skinny-dipping frogs.