"The Abdominal Viscera <em>in situ</em>, as seen when the abdomin is laid open and the great omentum removed. The ribs on the right side are indicated by Roman numerals; it will be observed that the eighth costal cartilage articulated with the sternum on both sides." &mdash;Encyclopedia Britannica, 1910

Abdomen

"The Abdominal Viscera in situ, as seen when the abdomin is laid open and the great omentum…

"The principal muscles are seen on the left, and superficial veins on the right." — Blaisedell, 1904

Principal Organs of the Thorax and Abdomen

"The principal muscles are seen on the left, and superficial veins on the right." — Blaisedell, 1904

"Tendons are white, glistening cords, or straps, which connect the muscles with the bones." &mdash; Blaisedell, 1904

Achillles tendon

"Tendons are white, glistening cords, or straps, which connect the muscles with the bones." —…

"The head is represented as having been thrown back, and the tongue drawn forward. <em>A</em>, <em>B</em> and <em>C</em>, cainine; <em>D, E</em> bicuspids; <em>F, H, K,</em> molars; <em>M</em> anterior pillar of the fauces; <em>N</em>, tonsil; <em>L</em> uvula; <em>O</em>, upper part of the pharynx; <em>P</em>, tongue drawn forward; <em>R</em> linear ridge, or raphe</em>." &mdash; Blaisedell, 1904

Back view of the adult mouth

"The head is represented as having been thrown back, and the tongue drawn forward. A, B

An illustration of the "ailmentary canal of Bluebird, reduced; after Audobon. a,b, gullet or oesophagus; c, proventriculus; d, gizzard; e, f, h, intestine; i, cloaca" (Forbush, 1907).

Ailmentary Canal of Bluebird

An illustration of the "ailmentary canal of Bluebird, reduced; after Audobon. a,b, gullet or oesophagus;…

"To illustrate roughly the passage of air through the glottis, force air through such a tube by blowing hard, and if the strips are not too far apart a sound will be produced. The sound will vary in character as the bands are made tight or loose." &mdash; Blaisedell, 1904

Air Passage

"To illustrate roughly the passage of air through the glottis, force air through such a tube by blowing…

"Diagram showing the capillary network of the air sacs and origin of the pulmonary veins.. <em>A</em>, small branch of pulmonary artery; <em>B</em>, twigs of pulmonary artery; <em>C</em>, capillary network around the walls of the air sacs; <em>D</em>, branches of network converging to form the veinlets of the pulmonary veins." — Blaisedell, 1904

Capillaries of the Air Sac

"Diagram showing the capillary network of the air sacs and origin of the pulmonary veins.. A,…

"<em>A</em>, epithelial lining wall; <em>B</em>, partition between two adjacent sacs, in which run capillaries; <em>C</em>, fibers of elastic tissues." &mdash; Blaisedell, 1904

Diagrammatic view of an air sac

"A, epithelial lining wall; B, partition between two adjacent sacs, in which run capillaries;…

Left wing of the albatross.

Left Wing of Albatross

Left wing of the albatross.

"<em>A</em>, a portion of the colon laid open to show the valve between the large and small intestine; <em>B</em>, the caecum." &mdash; Blaisedell, 1904

Vermiform appendix

"A, a portion of the colon laid open to show the valve between the large and small intestine;…

Arm.

Arm

Arm.

Arm.

Arm

Arm.

Shows the muscles and tendons of the arm.

Muscle structure of the arm

Shows the muscles and tendons of the arm.

"Muscles on the front of the arm. Note the while cords, the tendons at the wrist." &mdash;Davison, 1910

Muscles of the arm

"Muscles on the front of the arm. Note the while cords, the tendons at the wrist." —Davison, 1910

"The Right Axillary and Branchial Arteries, with Some of their Main Branches." &mdash; Blaisedell, 1904

Arteries

"The Right Axillary and Branchial Arteries, with Some of their Main Branches." — Blaisedell, 1904

"Showing how firm pressure may be made with the fingers to compress the branchial artery of the left arm. Some large superficial veins are also shown." &mdash; Blaisedell, 1904

Branchial artery

"Showing how firm pressure may be made with the fingers to compress the branchial artery of the left…

"The dotted line shows the course of the right femoral artery." &mdash; Blaisedell, 1904

Femoral artery

"The dotted line shows the course of the right femoral artery." — Blaisedell, 1904

"The Femoral Artery of Right Leg." &mdash; Blaisedell, 1904

Leg artery

"The Femoral Artery of Right Leg." — Blaisedell, 1904

"Artery in the Front of the Right Leg." &mdash; Blaisedell, 1904

Leg artery

"Artery in the Front of the Right Leg." — Blaisedell, 1904

"View from above of the Atlas, the first cervical vertebra."&mdash;Finley, 1917

Atlas

"View from above of the Atlas, the first cervical vertebra."—Finley, 1917

"Side view of the axis, the second cervical vertebra."&mdash;Finley, 1917

Axis

"Side view of the axis, the second cervical vertebra."—Finley, 1917

"Some of the Larger Muscles on the Back of the Shoulder and the Arm." &mdash; Blaisedell, 1904

Muscles of the back and shoulder

"Some of the Larger Muscles on the Back of the Shoulder and the Arm." — Blaisedell, 1904

"The spinal column below the twelfth dorsal vertebra at <em>A</em> has been removed, as well as the various layers of the great muscles of the back. The two kidneys with the renal arteries and veins are plainly shown, in their normal positions. The relative positions of adjacent vessels and organs with their names printed upon them are also shown. <em>B</em>, portion of the diaphragm on the left side; <em>C</em>, receptaculum chyli; <em>D</em>, a part of the small intestine on the left side." &mdash; Blaisedell, 1904

Vertical section of the back

"The spinal column below the twelfth dorsal vertebra at A has been removed, as well as the…

The bat genus Nyctalus (Noctule bats) are Evening bats. They are distributed in the temperate and subtropical areas of Europe, Asia and North Africa.

Skeleton and Wing Membranes of the Noctule Bat

The bat genus Nyctalus (Noctule bats) are Evening bats. They are distributed in the temperate and subtropical…

Beak of Buzzard.

Buzzard Beak

Beak of Buzzard.

Beak of Hawfinch.

Hawfinch Beak

Beak of Hawfinch.

Beak of Hummingbird.

Hummingbird Beak

Beak of Hummingbird.

Beak of Tawny Owl.

Owl Beak

Beak of Tawny Owl.

Beak of Shrike.

Shrike Beak

Beak of Shrike.

Beak of Swift.

Swift Beak

Beak of Swift.

The antenna of the honey-bee.

Honey Bee

The antenna of the honey-bee.

The mandible of the honey-bee.

Honey Bee

The mandible of the honey-bee.

The head of the honey-bee.

Honey Bee

The head of the honey-bee.

The prothorax of the honey-bee.

Honey Bee

The prothorax of the honey-bee.

The tongue of the honey-bee.

Honey Bee

The tongue of the honey-bee.

The mesothorax of the honey-bee.

Honey Bee

The mesothorax of the honey-bee.

The metathorax of the honey-bee.

Honey Bee

The metathorax of the honey-bee.

The abdomen of the honey-bee.

Honey Bee

The abdomen of the honey-bee.

The larva of the honey-bee.

Honey Bee

The larva of the honey-bee.

The pupa of the honey-bee.

Honey Bee

The pupa of the honey-bee.

The pupa of the honey-bee.

Honey Bee

The pupa of the honey-bee.

"The structure of the mouth in insects exhibits very remarkable modifications, and these are of the utmost importance in the classification of these creatures. In some insects the mouth is formed exclusively for biting; in others, as exclusively for suction; while in others again it is fitted for the performance of both these actions; and the form of its constituent parts of course undergoes corresponding changes; but the same organs really exist in all, modified in apearance, indeed, so as sometimes to be scarecely recognizable." &mdash; Goodrich, 1859

Mouth and Tongue of a Bee

"The structure of the mouth in insects exhibits very remarkable modifications, and these are of the…

A species of beetle found in tropical Africa.

Centaur Beetle

A species of beetle found in tropical Africa.

"Under surface of large beetle, with deeply concave and comparatively small wings, shows that the nervures of the wings of the beetle are arranged along the anterior margins and throughout the substance of the wings generally, very much as the bones of the arm, forearm, and hand, are in the wings of the bat, to which they bear a very marked resemblance, both in their shape and mode of action."&mdash;Pettigrew, 1874

Large Beetle

"Under surface of large beetle, with deeply concave and comparatively small wings, shows that the nervures…

The prothorax of the May beetle.

May Beetle

The prothorax of the May beetle.

The mesothorax of the May beetle.

May Beetle

The mesothorax of the May beetle.

The metathorax of the May beetle.

May Beetle

The metathorax of the May beetle.

The abdomen of the May beetle.

May Beetle

The abdomen of the May beetle.

The metathorax of the May beetle from the front.

May Beetle

The metathorax of the May beetle from the front.

The May beetle larva in a burrow.

May Beetle

The May beetle larva in a burrow.

A pupa of the May beetle.

May Beetle

A pupa of the May beetle.

A pupa of the May beetle in cocoon.

May Beetle

A pupa of the May beetle in cocoon.

An illustration of the dorsal view of a stag beetle.

Stag Beetle (Dorsal)

An illustration of the dorsal view of a stag beetle.

External features of a bird.

Bird

External features of a bird.

"Shows how the bones of the arm (a), forearm (b), and hand (c), are twisted, and form a conical screw."&mdash;Pettigrew, 1874

Wing of Bird

"Shows how the bones of the arm (a), forearm (b), and hand (c), are twisted, and form a conical screw."—Pettigrew,…

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

"A single muscle rarely or never contracts alone, but always in harmony with a number of other muscles. Even the simplest movement we can make requres the combined action of several muscles to carry it out. If the movement is at all difficult, such as playing on the piano or riding on the bicycle, the different muscles must contract in a certain order and with a certain strength and rapidity." &mdash; Blaisedell, 1904

Superficial muscles of the body

"A single muscle rarely or never contracts alone, but always in harmony with a number of other muscles.…

The bowfin, a primitive freshwater fish, also known as the freshwater dogfish is a voracious fish.

Bowfin

The bowfin, a primitive freshwater fish, also known as the freshwater dogfish is a voracious fish.

<em>A</em>, anterior lobe of the cerebellum; <em>B</em>, olfactory nerve; <em>C</em>, portion of the posterior lobe; <em>D</em>, optic chiasm; <em>E</em>, optic tract; <em>H, M,</em> hemispheres of the cerebellum; <em>K</em>, portion of the occipital lobe; <em>N</em>, medulla oblongata; <em>R</em>, pons Varolii."

Base of the brain

A, anterior lobe of the cerebellum; B, olfactory nerve; C, portion of the…

"Arteries and their Branches at the Base of the Brain." &mdash; Blaisedell, 1904

Blood vessels of the brain

"Arteries and their Branches at the Base of the Brain." — Blaisedell, 1904