The hyoid, os hyoides, or tongue bone, is an isolated, U-shaped bone lying in front of the throat, just above the Adam's apple; it supports the tongue, and give attachment to some of its numerous muscles.

Human Hyoid Bone

The hyoid, os hyoides, or tongue bone, is an isolated, U-shaped bone lying in front of the throat, just…

An illustration of an Ichthyosaurus skeleton. Ichthyosaurus is an extinct genus of ichthyosaur from the Early Jurassic (Hettangian - Sinemurian) of Europe (Belgium, England and Germany). It is among the best known ichthyosaur genera, with the Order Ichthyosauria being named after it. Ichthyosaurus was the first complete fossil to be discovered in the early 1800's by Mary Anning in England.

Archaeopteryx Skeleton

An illustration of an Ichthyosaurus skeleton. Ichthyosaurus is an extinct genus of ichthyosaur from…

Part of the skeletal structure of a lithisdid silicious sponge.

Jereiea Polystoma

Part of the skeletal structure of a lithisdid silicious sponge.

A simple complete joint, one type of movable articulation. The synovial membrane is represented by dotted lines. They have a secreting membrane placed between their opposing surfaces, which keeps them well lubricated and capable of free movement one upon the other.

A Simple Complete Joint

A simple complete joint, one type of movable articulation. The synovial membrane is represented by dotted…

A toothed, or dentated suture. This is one type of immovable articulation. It is found in the union of the cranial bones of the skull, such as the suture between the frontal and parietal bones.

Human Joint, Dentated Suture

A toothed, or dentated suture. This is one type of immovable articulation. It is found in the union…

A mixed articulation (slightly movable). In this form, the bony surfaces are usually joined together by broad, flattened disks of fibro-cartilage, as in the articulations between the bodies of the vertebrae. Labels: a, b, disk of fibro-cartilage; c, articular cartilage; d, bone.

Human Joint, Mixed Articulation

A mixed articulation (slightly movable). In this form, the bony surfaces are usually joined together…

"Skeleton of hind foot of Kangaroo." —The Encyclopedia Britannica, 1910

Kangaroo Skeleton

"Skeleton of hind foot of Kangaroo." —The Encyclopedia Britannica, 1910

"The Knight and the Lady. By Albrecht Dürer. From the engraving on copper." -Heath, 1901

The Knight and the Lady

"The Knight and the Lady. By Albrecht Dürer. From the engraving on copper." -Heath, 1901

Lachrymal Bone. The lachrymal are the smallest and most fragile bones fo the face. They are situated at the front part of the inner wall of the orbit.

Human Lachrymal Facial Bone

Lachrymal Bone. The lachrymal are the smallest and most fragile bones fo the face. They are situated…

Malar (cheek) bone. The malar bones form the prominence of the cheek, and part of the outer wall and floor of the orbit.

Human Malar (Cheek) Bone

Malar (cheek) bone. The malar bones form the prominence of the cheek, and part of the outer wall and…

"Restored skeleton of Mammoth (Elephas primigenius)." —The Encyclopedia Britannica, 1903

Mammoth

"Restored skeleton of Mammoth (Elephas primigenius)." —The Encyclopedia Britannica, 1903

This illustration shows the skeletons of Anthropid Apes compared with that of Man.

Man and Ape Skeletons

This illustration shows the skeletons of Anthropid Apes compared with that of Man.

Superior maxillary bone. With it's fellow on the opposite side, it forms the whole of the upper jaw. Each bone assists in forming part of the floor of the orbit, the floor and outer wall of the nasal fossae, and the greater part of the roof of the mouth. Labels: 1, orbital surface; 2, facial surface; 3, alveolar process.

Human Maxillary (Upper Jaw) Bone

Superior maxillary bone. With it's fellow on the opposite side, it forms the whole of the upper jaw.…

Inferior Maxillary Bone (lower jaw). It is the largest and strongest bone in the face and serves for the reception of the lower teeth.

Human Maxillary (Upper Jaw) Bone

Inferior Maxillary Bone (lower jaw). It is the largest and strongest bone in the face and serves for…

Megatherium ("Great Beast") was a genus of elephant-sized ground sloths that lived from two million to 8,000 years ago. A related genus was Nothrotheriops, which were primarily bear-sized ground sloths. The rhinoceros-sized Promegatherium is suggested to be the ancestor of Megatherium.

Megatherium Skeleton

Megatherium ("Great Beast") was a genus of elephant-sized ground sloths that lived from two million…

"Skeleton of Mesohippus bairdi, the three-toed ancestor of our horse. This animal was about the size of a sheep." — Davison, 1906

Skeleton of a mesohippus bairdi

"Skeleton of Mesohippus bairdi, the three-toed ancestor of our horse. This animal was about the size…

The partial skeleton of a moa, an enormous flightless bird once native to New Zeland, now extinct.

Moa skeleton

The partial skeleton of a moa, an enormous flightless bird once native to New Zeland, now extinct.

"Skeleton of the Ateles Beleebuth." — Encyclopedia Britanica, 1893

Monkey Skeleton

"Skeleton of the Ateles Beleebuth." — Encyclopedia Britanica, 1893

Roman personification of death

Mors

Roman personification of death

"Skeleton of the Mylodon robustus." —The Encyclopedia Britannica, 1903

Mylodon Robustus

"Skeleton of the Mylodon robustus." —The Encyclopedia Britannica, 1903

Inferior turbinated bone, convex surface. The inferior turbinated bones are situated on the outer wall of each side of the nostril. Teach consists of a layer of thin, spongy bone, curled upon itself like a scroll.

Human Nostril Bone

Inferior turbinated bone, convex surface. The inferior turbinated bones are situated on the outer wall…

Occipital bone of the human skull, inner surface. It is situated at the back and base of the skull. Labels: 9,9, and 10,10, depression for reception of lobes of brain; 11, foramen magnum.

Occipital Bone of the Human Skull

Occipital bone of the human skull, inner surface. It is situated at the back and base of the skull.…

"Shows the powerful legs, small feet, and rudimentary wings of the bird; the obliquity at which the bones of the legs and wings are placed, and the comparatively small angles which two bones make at their point of junction."—Pettigrew, 1857

Skeleton of Ostrich

"Shows the powerful legs, small feet, and rudimentary wings of the bird; the obliquity at which the…

"Restoration of Palaeotherium." —The Encyclopedia Britannica, 1903

Palaeotherium

"Restoration of Palaeotherium." —The Encyclopedia Britannica, 1903

Palate bone. Palate bones form the back part of the roof of the mouth; part of the floor and outer wall of the nasal fossae, and a very small portion of the floor of the orbit.

Human Palate Bone

Palate bone. Palate bones form the back part of the roof of the mouth; part of the floor and outer wall…

Parietal bone of the human skull, inner surface. The parietal bones form the greater part of the sides and roof of the skull. Labels: A, parietal depression; E, furrow for ramification of arteries.

Parietal Bone of the Human Skull

Parietal bone of the human skull, inner surface. The parietal bones form the greater part of the sides…

"The Pedlar. By Holbein. From the Dance of Death." —D'Anvers, 1895

The Pedlar

"The Pedlar. By Holbein. From the Dance of Death." —D'Anvers, 1895

The Os Innominatum, or nameless bone, so called from bearing no resemblance to any known object, is a large irregular shaped bone, which, with its fellow of opposite side, forms the sides and front wall of the pelvic cavity. Labels: R, O, crest of ilium, just below O is seen the anterior superior spinous process; J, tuberosity of ischium; t, part of pubes, between J and T is seen the thyroid foramen: H, acetabulum, below H is seen end of ubic bone which, with its fellow of opposite side, forms the symphysis pubis.

Part of the Human Pelvic Bone

The Os Innominatum, or nameless bone, so called from bearing no resemblance to any known object, is…

Male pelvis (top) and female pelvis (bottom). The pelvis is stronger and more massively constructed than either the cranial or thoracic cavity. It is composed of 4 bones, the ossa innominata, forming sides and front, and the sacrum and coccyx, completing it behind. The female pelvis differs from that of the male in making it better adapted for giving birth. The most notable differences are that the female pelvis is wider in every direction, giving more room for the child to pass and shallower, which lessens the distance through which the child has to be propelled; and lastly, the bones are thinner and smoother.

Human Pelvis, Male and Female

Male pelvis (top) and female pelvis (bottom). The pelvis is stronger and more massively constructed…

"The bones of fishes are of a less dense and compact nature than in the higher order of animals; in some, indeed, they are wholly cartilaginous. The skeleton may in general be divided into four chief parts - the Vertical Column, the Head, the Repiratory Apparatus, and the Limbs" — Goodrich, 1859

Perch skeleton

"The bones of fishes are of a less dense and compact nature than in the higher order of animals; in…

"The spinal column consists of abdominal and caudal vertebre, the coalescence of the parapophyses into a complete hemal ring and the suspension of the anal fin generally forming a sufficiently well-marked boundary between the abdominal and caudal regions." — Encyclopedia Britannica, 1893

Perch Skeleton

"The spinal column consists of abdominal and caudal vertebre, the coalescence of the parapophyses into…

The skeleton of a perch.

Skeleton of Perch

The skeleton of a perch.

An illustration of the skeleton of a pezophaps solitarius, part of the dodo family.

Pezophaps Solitarius (Skeleton)

An illustration of the skeleton of a pezophaps solitarius, part of the dodo family.

"Pectoral arch and fore limb of the pike (Esox lucius), an osseous fish, showing scapulocoracoid, composed of Scp, scapula or hypercoracoid; c, posterior end of the outer margin of the scapulocoracoid; b, b, 1, 2, 3, 4, 5, five fin-rays or radialia; a, actinosts or basalia." -Whitney, 1911

Pike Scapulocoracoid

"Pectoral arch and fore limb of the pike (Esox lucius), an osseous fish, showing scapulocoracoid, composed…

A remarkable genus of fossil lizards, peculiar to the Mesozoic strata. Its anomalous structure was long a puzzle to comparative anatomists.

Pterodactyl

A remarkable genus of fossil lizards, peculiar to the Mesozoic strata. Its anomalous structure was long…

"So peculiar and strange is the structure of these animals, that the first specimen discovered was classed by one naturalist as a bird, by another as a species of bat, and by yet a third as a flying reptile." — Goodrich, 1844

Pterodactyle skeleton

"So peculiar and strange is the structure of these animals, that the first specimen discovered was classed…

The radial bone in the human arm.

Radius

The radial bone in the human arm.

"The vertebre of serpents are so formed as to admit a great pliancy of the body, which is capable of being coiled up, with the head in the center of the coil, and some serpents have the power of throwing themselves to some distance from this coiled position." — Chambers, 1881

Rattlesnake Skeleton

"The vertebre of serpents are so formed as to admit a great pliancy of the body, which is capable of…

This is an illustration of the skeleton of a Rhinoceros.

Rhinoceros Skeleton

This is an illustration of the skeleton of a Rhinoceros.

"The <em>shoulder-blade</em> is a large, flat, three-sided bone, which is placed on the upper and back part of the chest. On the outer side it has a saucerlike cavity on which the rounded head of the arm bone rests." &mdash; Blaisedell, 1904

Scapula

"The shoulder-blade is a large, flat, three-sided bone, which is placed on the upper and back…

The human scapula bone (shoulder blade). Labels: 1, glenoid cavity; 2, end of the spine of scapula.

The Human Scapula

The human scapula bone (shoulder blade). Labels: 1, glenoid cavity; 2, end of the spine of scapula.

"The prey of a serpent is oven thicker than the serpent itself, and to admit of its being swallowed, the throat and body are very dilatable. The bones of the head are adapted to the necessity of a great expansion of the mouth and dilation of the throat." &mdash; Chambers, 1881

Serpent Head

"The prey of a serpent is oven thicker than the serpent itself, and to admit of its being swallowed,…

"A joint involving the principle of the shackle. Specifically, in anatomy, a kind of articulation found in the exoskeleton of some fishes, formed by the passing of a bony ring of one part through a perforation of another part, the two being thus movably linked together." &mdash;Whitney, 1889
<p>This illustration shows the shackle joint of a large spine with a bony plate of the skin of a siluroid fish.

Shackle Joint from the Exoskeleton of a Siluroid Fish

"A joint involving the principle of the shackle. Specifically, in anatomy, a kind of articulation found…

"The Scapula, or shoulder blade, is one of the two bones, the other being the clavicle, which form the pectoral arch or shoulder girdle." &mdash;Finley, 1917

Shoulder blade

"The Scapula, or shoulder blade, is one of the two bones, the other being the clavicle, which form the…

The Human Skeleton. Labels: a, parietal bone; b, frontal; c, cervical vertebrae; d, sternum; e, lumbar vertebrae; f, ulna; g, radius; h, wrist or carpal bones; i, metacarpal bones; k, phalanges; l, tibia; m, fibula; n, tarsal bones; o, metatarsal; p, phalanges; , patella; r, femur; s, haunch (hip) bone; t, humerus; u, clavicle.

The Human Skeleton

The Human Skeleton. Labels: a, parietal bone; b, frontal; c, cervical vertebrae; d, sternum; e, lumbar…

The framework of animals, which in vertebrates is composed of bone and cartilage. It serves to support the fleshy parts and the nervous system, and forms levers for the muscles.

Skeleton

The framework of animals, which in vertebrates is composed of bone and cartilage. It serves to support…

A human skeleton

Skeleton

A human skeleton

The bony and cartilaginous skeleton.

Human Skeleton, Showing Bony and Cartilage Tissue

The bony and cartilaginous skeleton.

The human skeleton.

Human Skeleton

The human skeleton.

The skeleton.

The Skeleton

The skeleton.

A diagram of the human skeleton.

The Human Skeleton

A diagram of the human skeleton.

General view of the human skeleton.

Skeleton

General view of the human skeleton.

"Ideal plan of the double-ringed body of a vertebrate. N, neural canal; H, haemal canal; the body separating them is the centrum of any vertebra, bearing e, and epapophysis, and y, a hypapophysis; n, n, neurapophyses; d, d, diapophyses; ns, bifid neural spine; pl, pl, pleurapophyses; h, h, haemapophyses; hs, bifid haemal spine. Drawn by Dr. R. W. Shufeldt, USA, After Owen. The Axial Skeleton of a bird or any vertebrated animal, that is, one having a back-bone, exhibits in cross-section two rings or hoops, one above and the other below a central point, like the upper and lower loops of a figure 8. The upper ring is the neural arch, so called because such cylinder encloses a section of the cerebro-spinal axis, or principal nervous system of a vertebrate (brain and spinal cord, whence arise all the nerves of the body, excepting those of the sympathetic nervous system). The lower ring is the haema arch, which similarly contains a section of the principal blood vessals and viscera.

Axial Skeleton

"Ideal plan of the double-ringed body of a vertebrate. N, neural canal; H, haemal canal; the body separating…

A human skeleton from the back.

Back View of a Human Skeleton

A human skeleton from the back.

In the bat, the forelimbs are much longer than the hindlimbs and have several of the fingers greatly lengthened.

Bat Skeleton

In the bat, the forelimbs are much longer than the hindlimbs and have several of the fingers greatly…

An illustration of a bird skeleton.

Bird Skeleton

An illustration of a bird skeleton.

The bony and cartilaginous skeleton.

The Bony and Cartilaginous Skeleton

The bony and cartilaginous skeleton.

"The skeleton, more especially in the higher forms, is in the main similar to that of man, so that only a brief notice is necessary. In the skull considerable variation in regard to the proportionate length of the face to that of the brain&mdash;case (cranial portion) exists in the two sexes, owing to the general development of large tusks in the males." &mdash; Encyclopaedia Britannica Company, 1910

Chacma Baboon Skeleton

"The skeleton, more especially in the higher forms, is in the main similar to that of man, so that only…

Front view of the human skeleton.

Skeleton, Front View

Front view of the human skeleton.

"The greatest absolute length of the fore&mdash;limb occurs in the gorilla and the orangutan. The humerus never has a perforation on the inner side of its lower extremity. Except in the man&mdash;like apes, the ulna articulates with the wrist (carpus). The hand is capable of pronation and supination on the fore&mdash;arm; and except in man, the chimpanzee and the gorilla there is a centrale in the carpus." &mdash;Encyclopaedia Britannica, 1910

Front View of Gorilla Skeleton

"The greatest absolute length of the fore—limb occurs in the gorilla and the orangutan. The humerus…