1. Olfactory Bulb. 2. Second, or Optic Nerves. 3. Anterior Perforated Space. 4. Optic Tract. 5. Crus Cerebri. 6. 3d Nerve. 7. 4th Nerve. 8. 5th Nerve. 9. 6th Nerve. xii A COMPEND OF ANATOMY. Define the term Anatomy. Derived from the Greek dva ana, through, and répvɛw temnein, to cut, it strictly means dissection, but is technically applied to that science which treats of the structure of organized bodies. What are the divisions of Descriptive Human Anatomy? They are,Osteology, the anatomy of the bones; Syndesmology, of the joints; Myology, of the muscles; Angiology, of the vessels; Neurology, of the nerves; Splanchnology, of the internal viscera; Adenology, of the glands; Dermatology, of the skin; Genesiology, of the generative organs. State the number of Bones in the Adult Human Skeleton. It is variously stated by different anatomists. Excluding the teeth, the Wormian and sesamoid bones, and the ossicles of the middle ear, the whole number would be 200; excluding also the 2 patellæ, and the hyoid bone, would leave in the skeleton proper 197 bones. Describe the Long Bones. They number 90, act as supports, or levers, and are known by having a medullary canal in the centre of each, a shaft (diaphysis), and two extremities. They are developed by osseous deposit in cartilage. Describe the Short Bones. is required, but limited motion. in cartilage. Numbering 30, they are found where strength Describe the Flat Bones. They number 38, protect the viscera by forming walls around them, and afford extensive attachment for muscles. They are developed by osseous deposit in membranes, and consists of 2 dense layers, separated by a cellular or cancellated osseous tissue, the diploë. What are the Irregular Bones? They are 39 in number, and include the vertebræ, sacrum, coccyx, the temporal, ethmoid, and sphenoid bones, and the bones of the face, except the nasal, lachrymal, and vomer. 9 Name the Bones of the Head. They number 22, and comprise theCranial Bones (8)-the frontal, 2 parietal, occipital, 2 temporal, the sphenoid and the ethmoid bones. Facial Bones (14)—2 superior maxillary, 2 malar, 2 nasal, 2 lachrymal, 2 palate, 2 inferior turbinated, vomer and inferior maxillary. Name the Bones of the Trunk. They number 53, as follows, viz.— Vertebræ (24)—7 cervical, 12 dorsal, and 5 lumbar vertebræ. Thorax (25)—7 pairs of true ribs, 3 pairs of false ribs, 2 pairs of floating ribs, (articulating with the bodies of the dorsal vertebræ,) and the sternum. Pelvis (4)—the sacrum, the coccyx, and 2 ossa innominata; each os innominatum consisting of 3,-the ilium, ischium, and pubes. Name the Bones of each Upper Extremity. They number 32, as follows: Shoulder (2)-the clavicle and scapula. Arm (1)—the humerus. Forearm (2)-the radius and ulna. Hand (27)-8 carpal bones,-the scaphoid, semilunar, cuneiform, pisiform, trapezium, trapezoid, os magnum, and unciform,-5 metacarpal, and 14 phalanges. Name the Bones of each Lower Extremity. They number 29, viz.Thigh (1)-the femur. Leg (the tibia and fibula. Foot (26)-7 tarsal bones,—the astragalus, os calcis, scaphoid, cuboid, external middle and internal cuneiform,-5 metatarsal, 14 phalanges. Name the Unclassified Bones. They are the— Patella (2), which are sesamoid bones, each developed in the tendon of the quadriceps extensor femoris muscle. Hyoid Bone (1)—the tongue-bone, not articulated to the skeleton. Malleus, Incus, Stapes (3 pairs)-the bones of the middle ear. Sesamoid Bones, of variable number, situated in the tendons of the gastrocnemius and peroneus longus muscles, and in the flexor tendons of the great toe and the thumb. Wormian Bones (ossa triqueta), sometimes found in the cranial sutures, are not constant in number or size. Name the principal Eminences on Bones. Heads, are convex and smooth, for articulation in movable joints. Condyles, are irregularly-shaped heads. Trochanters, when for turning the bone. Tuberosities, are broad, uneven prominences. Tubercles, are small tuberosities. Spines, or Spinous processes, when sharp and slender. (Apophysis, is a process which has been an Epiphysis, or separated from the shaft by cartilage, but has become united thereto by ossification (?) What other names are given to Bony Prominences? There are several adjectives applied to them from their fancied resemblances, such asAzygos, without a fellow; Clinoid, like a bed; Coracoid, like a crow's beak; Coronoid, like a crown; Hamular, hook-like; Malleolar, like a mallet; Mastoid, like a nipple; Odontoid, tooth-like; Pterygoid, wing-like; Rostrum, a beak; Spinous, thorn-like; Styloid, pen-like; Squamous, scaly; Vaginal, ensheathing, etc. Name the Cavities of Bones. Articular cavities are called Cotyloid, cuplike; Glenoid, shallow; Trochlear, pulley-like; Facet, if smooth; Alveolar, or Alveoli, when socket-like. Non-articular cavities are named fossæ, sinuses, aqueducts, foramina, canals, fissures, notches, cells, grooves, depressions, etc. What is the Composition of Bone? Organic or animal matter, about 3, consisting of gelatin, vessels and fat. Inorganic, or mineral, about 2/3, consisting of phosphate and carbonate of calcium (62 per cent.), with fluoride of calcium, phosphates of magnesium, sodium, and chloride of sodium (4 per cent.). Heat will remove the organic matter and leave the inorganic; dilute Nitric or Hydrochloric acid will remove the inorganic, and leave the organic. In old age the inorganic constituents predominate, and the bones are brittle; in youth the organic predominate, and epiphyseal dislocation is more common than fracture, especially in the long bones of the extremities. Describe the Structure of Bone. Bone is composed of an outer compact layer, and an inner cellular or spongy structure. It is surrounded, except at the articular cartilages, by a vascular fibrous membrane, the Periosteum, which receives the insertions of all tendons, ligaments, etc.; and the central cavity of long bones is lined by a similar structure, the Endosteum. A transverse section of bone, examined microscopically, shows Haversian Canals, diameter inch, for the passage of vessels. Canaliculi, diameter 16 inch, radiating from the canals, and connecting them with the lacunæ. Lacuna, arranged circularly around the canals, and contain the bone-cells, appearing as irregular dark spaces. Haversian Spaces, connect the canals with the medullary spaces, and divide Circumferential Lamellæ, are bone layers binding the canals together. |