SPECIAL A. (styled descriptive by the French writers) treats of the several parts and organs of the body in respect to their form, structure, and systematic connection or relation with each other. The arrangement of the several parts and organs in an order deduced from their similarity in structure or use, constitutes SYSTEMATIC A. According to this mode of study, which is essential as an introduction to physiology, A. has been divided, though not with scientific precision, into six branches of study. 1. Osteology, which treats of the bones, including the cartilages of the joints (chondrology).-2. Syndesmology, which describes the ligaments, or bands, that unite the bones of various joints. The bones, with their cartilages and ligaments, form a framework, which supports the exter nal soft parts, and within which the vital organs are suspended and protected from injury; they are also arranged in a mechanical system as instruments of motion.-3. Myology explains the system of the muscles, which, by their contractile power, serve to impart motion to the bones and joints; while, like the bones, they contribute to form the cavities of the body, and to protect the internal organs. Their structure also serves to produce the external shape and symmetry.-4. Angelology describes the vessels or ducts, with their complex net-work and ramifications, spreading over most parts of the body, and divided into two great systems: (a), the blood-vessels with the heart, a fleshy organ propelling the blood through the pulsating vessels or arteries, from which it returns to the heart, after circulation through the veins; (b), the lymphatics, by which a certain fluid (lymph) is brought into union with the blood in the organs styled lymphatic glands, and is afterwards passed into the veins.--5. Neurology, or the doctrine of the nerves, describes the nervous system, as divided into first, the two central masses of the brain and the spinal column; second, the ramification of nerves running from the brain and spinal column to almost all points of the surface; and lastly, the order of nerves having a peculiar structure, and styled the ganglionic system of nerves.-6. Splanclinology describes the viscera, or organs formed by combination of the distinct systems of veins, nerves, lymphatics, etc., and mostly situated in the cavities of the body. These are divided into five groups, viz.: (a), the organs of sensation—sight, hearing, smell, taste, and touch; (b), of voice and respiration—nostrils, mouth, larynx, trachea, and lungs, with the thyroid gland. the thymus gland, and the diaphragm; (e), digestive organs—the mouth,
with its salivary glands, the throat, gullet, the stomach, the intestines, with the liver, spleen, and pancreas; (d), the urinary organs—kidneys, ureter, bladder, and urethra; (e), sexual organs of both sexes.
Special A. may be treated in another made; by an arrangement made in accordance with natural divisions, or by imaginary lines dividing the body into several regions—as the head, the trunk, and the extremities. Again, the trunk may be subdivided into neck, thorax, and abdomen; and in each of the main regions, several subdivisions may be made. This system of arrangement may be styled TOPOGRAPHICAL A., and is also known as SURGICAL A., on account of its importance as the basis of operative surgery. It was the eldest of the Monroes of Edinburgh University who first gave this branch of the study its due prominence.
The several parts and organs of the animal body will be found described under their proper heads.
History of A.—It is difficult to determine the date at which this science began to be cultivated, but it probable that from the earliest times some persons took advantage of favorable circumstances to acquaint themselves with it. The Druids, who were at once the priests, judges, and physicians of the people, demanded from those who came for their advice human victims as sacrifices, and were themselves the executioners; and it is not unlikely that they availed themselves of these opportunities of acquiring anatomical knowledge. It is probable, says Galen, that .tEsculapius, who excelled in the treatment of wounds, dissected animals for the instruction of his pupils. His descendants, the ' Asclepiades, cultivated A., or rather zootomy, and founded the three famous schools of Cos, Rhodes, and Cnidos. The rabbins tell us that, although among the Jews the touching of a dead body involved ceremonial uncleanness, they did not entirely neglect A., which they studied from the carefully preserved bones of their ancestors, and the ; necessary manipulations of embalming. They counted 248 bones, and 365 veins or ligaments, which division, according to the rabbins, has relation to the 248 precepts of the Mosaic law that command, and the 365 that forbid.