"Under Surface of Head of Tumble-bug (Copris carolina), about four times natural size. 1, galea; 2, palpifer; 3, lacinia; 4, subgalea; 5, maxillary palp; 6, stipes." -Whitney, 1911

Ventral View of Dung Beetle

"Under Surface of Head of Tumble-bug (Copris carolina), about four times natural size. 1, galea; 2,…

The ventral and dorsal view of the pupa of Erotylus boisduvali, a fungus beetle.

Fungus Beetle Pupa

The ventral and dorsal view of the pupa of Erotylus boisduvali, a fungus beetle.

An illustration of the under of a stag beetle.

Beetle, Stag (Ventral)

An illustration of the under of a stag beetle.

"Burbot (Lota vu'garis), with jugular ventral fins." — Encyclopedia Britannica, 1893

Burbot

"Burbot (Lota vu'garis), with jugular ventral fins." — Encyclopedia Britannica, 1893

A ventral view of a chiton, showing p, foot; o, mouth; kr, oval fringe; and br, the numerous ctenidia. Chitons are small to large, primitive marine mollusks in the class Polyplacophora. There are 900 to 1,000 extant species of chitons in the class, which was formerly known as Amphineura. Chitons have a shell which is composed of eight separate shell plates or valves. These plates overlap somewhat at the front and back edges, and yet the plates articulate well with one another. Because of this, although the plates provide good protection for impacts from above, they nonetheless permit the chiton to flex upward when needed for locomotion over uneven surfaces, and also the animal can slowly curl up into a ball when it is dislodged from the underlying surface. The shell plates are surrounded by a structure known as a girdle.

Chiton (Ventral)

A ventral view of a chiton, showing p, foot; o, mouth; kr, oval fringe; and br, the numerous ctenidia.…

An illustration of the dorsal view of a chiton with the shell removed. Showing b, buccal mass; ov, ovary; od, oviduct; i, coils of intestine; ao, aorta; c' keft testine; and c, ventricle.

Chiton with Shell Removed

An illustration of the dorsal view of a chiton with the shell removed. Showing b, buccal mass; ov, ovary;…

"Fig. 24. - Pterylosis of Cyoselus apus, drawn by Coues after Nitzsch; right hand upper, left hand lower, surface. 1 spinal tract; 2. humeral; 3. femoral; 4. capital; 5. alar; 6. caudal; 7. crural; 8. ventral." Elliot Coues, 1884

Pterylosis of Cypselus Apus

"Fig. 24. - Pterylosis of Cyoselus apus, drawn by Coues after Nitzsch; right hand upper, left hand lower,…

"The spinal cord and medulla oblongata. A, from the ventral, and B, from the dorsal aspect; C to H, cross-sections at different levels." —Martin, 1917

Medulla Oblongata

"The spinal cord and medulla oblongata. A, from the ventral, and B, from the dorsal aspect; C to H,…

"Mullus barbatus (Red Mullet), with thoracic ventral fins." — Encyclopedia Britannica, 1893

Red Mullet

"Mullus barbatus (Red Mullet), with thoracic ventral fins." — Encyclopedia Britannica, 1893

"Diagram showing the muscular system. M, ventral, N, dorsal valve; l, loop; V, mouth; Z, extremity of intestine; a, adductor; c, divaricators; c', accessory divaricators; b, ventral adjustors; c, peduncular muscles; b''', dorsal adjustors; P, peduncle." — Encyclopedia Britanica, 1893

Muscular System

"Diagram showing the muscular system. M, ventral, N, dorsal valve; l, loop; V, mouth; Z, extremity of…

"The spinal cord and nerve-roots. A, a small portion of the cord seen from the ventral side; B, the same seen laterally; C, a cross-section of the cord; D, the two roots of a spinal nerve; 1, ventral fissure; 2, dorsal fissure; 3, surface groove along the line of attachment of the ventral nerve-roots; 4, line of origin of the dorsal roots; 5, ventral root filaments of spinal nerve; 6, dorsal root filaments; 6', ganglion of the dorsal root; 7, 7', the first two divisions of the nerve-trunk after its formation by the union of the two roots. The grooves are much exaggerated." —Martin, 1917

Nerve Roots

"The spinal cord and nerve-roots. A, a small portion of the cord seen from the ventral side; B, the…

"Development of notochord : msl, mesoblastic skeletogenous layer ; pdc, paired dorsal cartilage; pvc, paired ventral cartilage; ns, neautral spine; na, neutral arch; tp, transverse process; articular process; c, centrum."—Finley, 1917

Development of the notochord

"Development of notochord : msl, mesoblastic skeletogenous layer ; pdc, paired dorsal cartilage; pvc,…

"Fins of Common Perch. D, first dorsal; D', second dorsal; P, pectoral; V, ventral; A, anal; C, caudal." -Whitney, 1911

Fins of Common Perch

"Fins of Common Perch. D, first dorsal; D', second dorsal; P, pectoral; V, ventral; A, anal; C, caudal."…

"Salmo salar (Salmon), with abdominal ventral fins." — Encyclopedia Britannica, 1893

Salmon

"Salmo salar (Salmon), with abdominal ventral fins." — Encyclopedia Britannica, 1893

"A, Palate process of upper jawbone; B, zygoma, forming zygomatic arch; C, condyle, for forming articulation with atlas; D, foramen magnum; E, occipital bone" — Blaisedell, 1904

Base of skull

"A, Palate process of upper jawbone; B, zygoma, forming zygomatic arch; C, condyle, for forming articulation…

The anterior (ventral) surface of the sternum and the costal cartilages.

Sternum

The anterior (ventral) surface of the sternum and the costal cartilages.

"Longitudinal section of valves. A, ventral, B, dorsal valves; l, loop; q, crura; ss, septum; c, cardinal process." — Encyclopedia Britanica, 1893

Valves

"Longitudinal section of valves. A, ventral, B, dorsal valves; l, loop; q, crura; ss, septum; c, cardinal…

"Waldheimia flavescens. Interior of ventral valve. f, foramen; d, deltidium; t, teeth; a, adductor impressions; c, divaricator; d, accessory divaricators; b, ventral adjustor; b', peduncular muscle." — Encyclopedia Britanica, 1893

Ventral Valve

"Waldheimia flavescens. Interior of ventral valve. f, foramen; d, deltidium; t, teeth; a, adductor impressions;…