The superficial muscles in a horse.

Horse Muscles

The superficial muscles in a horse.

A diagram of the human muscular system.

A Diagram of the Human Muscular System

A diagram of the human muscular system.

"One of the Deep Layers of Muscles of the Neck and the Back." — Blaisedell, 1904

Muscles of the neck and back

"One of the Deep Layers of Muscles of the Neck and the Back." — Blaisedell, 1904

Muscles of the head, face, and neck.

Neck Muscles

Muscles of the head, face, and neck.

"Principal Muscles on the Left Side of the Neck." — Blaisedell, 1904

Muscles of the neck

"Principal Muscles on the Left Side of the Neck." — Blaisedell, 1904

"A Great Nerve (Crural) and its branches on the Front of the Thigh. The femoral artery with its cut end is shown." — Blaisedell, 1904

Great nerve

"A Great Nerve (Crural) and its branches on the Front of the Thigh. The femoral artery with its cut…

"Showing some of the superficial nerves on the left side of the neck and the head. A few superficial muscles and arteries in the same region are also shown." — Blaisedell, 1904

Superficial nerves of the head

"Showing some of the superficial nerves on the left side of the neck and the head. A few superficial…

"It is worthy of note that, owing to the oblique direction in which the muscles are commonly inserted into the bones, much of their force is lost so far as producing movement is concerned. Suppose the log of wood in the diagram to be raised by pulling on the rope in the direction a; it is clear at first that the rope will act at a great disadvantage; most of the pull transmitted by it will be exerted against the pivot on which the log hinges, and only a small fraction be available for elevating the latter. But the more the log is lifted, as for example into the position indicated by the dotted lines, the more useful will be the direction of the pull, and the more of it will be spend on the log and the less lost unavailingly in merely increasing the pressure at the hinge." —Martin, 1917

Oblique Pull

"It is worthy of note that, owing to the oblique direction in which the muscles are commonly inserted…

Half an Oyster Shell.

Oyster

Half an Oyster Shell.

The Pterygoid muscles, the zygomatic arch, and a portion of the ramus of the mandible have been removed.

Pterygoid Muscles

The Pterygoid muscles, the zygomatic arch, and a portion of the ramus of the mandible have been removed.

Left thigh-muscle of a rail.

Rail Thigh

Left thigh-muscle of a rail.

The muscles of the rear thigh. 1, fifth lumbar vertebra; 2, ilio-lumbar ligament; 3, crest of ilium; 4, anterior superior spinous process; 5, origin of fascia femoris; 6, gluteus medino; 7, its lower and anterior portion; 8, pyriformis; 9, gemini; 10, trochanter major; 11, insertion gluteus medius; 12, quadratus femoris; 13, adductor magnus; 14, insertion gluteus maximus; 15, vastus extensus; 16, long head biceps; 17, semimembranous; 18, semitendinosus; 19, tuber ischii; 20, obturator internus; 21, point of coccyx; 22, posterior coccygeal ligament; 23, 24, great sacro-sciatic ligament; 25, posterior superior spinous process; 26, posterior sacro-iliiac ligaments.

Rear Thigh Muscles

The muscles of the rear thigh. 1, fifth lumbar vertebra; 2, ilio-lumbar ligament; 3, crest of ilium;…

"Showing the attachment of the recti, or straight muscles to the eyeball, also the distribution of arteries upon the outer coat of the eye." — Blaisedell, 1904

Attachment of the recti

"Showing the attachment of the recti, or straight muscles to the eyeball, also the distribution of arteries…

"Diagram of the simple reflex arc. R, receptor; A, afferent (sensory) neuron; E, efferent (motor) meuron; M, muscle." —Martin, 1917

Reflex Arc

"Diagram of the simple reflex arc. R, receptor; A, afferent (sensory) neuron; E, efferent (motor) meuron;…

"View from below of a scorpion (Buthus occitanus) opened and dissected so as to show the pericardium with its muscles, the lateral arteries, and the tergo-sternal muscles. PRO, Prosoma. dpm, Dorso-plastral muscle. art, Lateral artery. tsm1, Tergo-sternal muscle of the second (pectiniferous) mesosomatic somite; this is the most anterior pair of the series of six, none are present in the genital somite. tsm4, Tergo-sternal muscle of the fifth mesosomatic somite. tsm6, Tergo-sternal muscle of the enlarged first metasomatic somite. Per, Pericardium. VPM1 to VPM7, The series of seven pairs of veno-pericardiac muscles. There is some reason to admit the existence of another more anterior pair of these muscles in Scorpio; this would make the number exactly correspond with the number in Limulus." — The Encyclopedia Britannica, 1910

Scorpion

"View from below of a scorpion (Buthus occitanus) opened and dissected so as to show the pericardium…

A snail shell.

Shell

A snail shell.

A pheasant sea shell.

Shell

A pheasant sea shell.

A mussel shell of the stone—boring genus Lithodomus.

Date Shell

A mussel shell of the stone—boring genus Lithodomus.

"A Portion of a Striped Muscular Fiber. Highly magnified. A, fiber separating into disks; B, fibrillae; C, cross-section of a disk." — Blaisedell, 1904

Striped muscular fiber

"A Portion of a Striped Muscular Fiber. Highly magnified. A, fiber separating into disks; B, fibrillae;…

"A Portion of Striped Muscular Fiber, showing Stripes and Nuclei. Highly magnified." — Blaisedell, 1904

Striped muscular fiber

"A Portion of Striped Muscular Fiber, showing Stripes and Nuclei. Highly magnified." — Blaisedell,…

The muscles involved in swallowing food and water.

Swallowing

The muscles involved in swallowing food and water.

"The circular muscle of the mouth (1) and the buccinator or trumpeter's muscle (2) help the tongue to push the food back to the upper margin of the gullet, where it is seized upon by the three constrictor muscles (3, 4 and 5) of the pharynx, and pushed down the gullet or esophagus, which is represented as being cut off at 6." — Richardson, 1906

Swallowing Muscles

"The circular muscle of the mouth (1) and the buccinator or trumpeter's muscle (2) help the tongue to…

The rectus muscle of the thigh; to show the constituent parts of a muscle. Labels: R, the fleshy belly; to, Tendon of origin; ti, Tendon of insertion; n, Nerve of supply; a, Artery of supply; v, Vein; l, Lymphatic vessel; P, the patella.

Thigh Muscle

The rectus muscle of the thigh; to show the constituent parts of a muscle. Labels: R, the fleshy belly;…

"Some of the Larger Muscles on the back of the Thigh. Powerful tendons at the hip and on the back of the knee are well shown." — Blaisedell, 1904

Thigh muscles

"Some of the Larger Muscles on the back of the Thigh. Powerful tendons at the hip and on the back of…

Muscles of the thigh.

Muscles of the Thigh

Muscles of the thigh.

Section of the head of a serpent. a, poison fangs; b, poison glands; c, conductor for the poison; d, muscles of the jaws; e, tendon of the muscles; s, salivary glands.

Cross section of a viper head

Section of the head of a serpent. a, poison fangs; b, poison glands; c, conductor for the poison; d,…

"Transverse section of an Alcyonarian zooid. mm, mesenteries; mb, muscle banners; sc, sulcus; st, stomodaeum." —Encyclopedia Britannica, 1910

Alcyonarian Zooid

"Transverse section of an Alcyonarian zooid. mm, mesenteries; mb, muscle banners; sc, sulcus; st, stomodaeum."…

"Diagrammtic longitudinal section of an Anthozoan zooid. m, Mesentery; t, Tentacles; st, Stomodaeum; sc, Sulcus; r, Rotteken's muscle; s, stoma; lm, Longitudinal muscle; d, diagonal muscle; go, gonads." —Encyclopedia Britannica, 1910

Anthozoan Zooid

"Diagrammtic longitudinal section of an Anthozoan zooid. m, Mesentery; t, Tentacles; st, Stomodaeum;…