The areolo-fibrous fascia is best illustrated by the common subcutaneous investment of the entire body, the superficial fascia. This structure is situated immediately beneath the integument over every part of the frame, and is the medium of connexion between that layer and the deeper parts; it is composed of areolar and elastic tissues, and contains an abundance of adipose cells. The fat, being a bad conductor of caloric, serves to retain the warmth of the body, while it forms at the same time a yielding tissue, through which minute vessels and nerves pass to the skin without incurring the risk of obstruction from injury or pressure.
The aponeurotic fascia is the strongest kind of investing membrane; it is composed of tendinous fibres running parallel with each other and connected by other fibres of the same kind passing in different directions, together with areolar tissue and fine elastic fibres. In the limbs, it constitutes the deep fascia, inclosing and forming distinct sheaths to all the muscles and tendons. It is thick on the outer and least protected side of the limb, and thinner at its inner side.
The Skin is the exterior investment of the body, which it serves to cover and protect. It is continuous at the aperture of the internal cavities with the lining membrane of those cavities, the internal skin or mucous membrane, and is composed essentially of two layers—derma and epidermis. The derma or cutis is chiefly composed of areola-fibrous tissues, besides which it has entering in its structure elastic tissues and smooth muscular fibre, together with blood vessels and nerves. The epidermis or cuticle (scarf-skin) is a product of the derma, which it serves to envelop and defend. That surface of the epidermis which is exposed to the influence of the atmosphere and exterior sources of injury is hard and horny in texture, while that which lies in contact with the under layer is soft and cellular.
Viscera.—The viscera of the human body are situated in the three great cavities—cranio-spinal, thorax and abdomen. The viscera of the cranio-spinal cavity are the brain, with the spinal cord, and the principal organs of sense. The viscera of the chest are, the central organs of circulation, the heart, the organs of respiration, the lungs. The abdominal viscera admit of a sub-division into those which properly belong to that cavity, viz.: the alimentary canal, the liver, pancreas, spleen and kidneys; and those of the pelvis, the bladder and the internal organs of generation.
Cartilage.—In the structure of joints, cartilages serve the double purpose of a connecting and separating medium; in the former capacity possessing great strength; in the latter, smoothness and elasticity. For instance, the costal cartilages unite the ribs with the sternum and form the point of separation by the knife, when it is desired to raise the sternum, as in the preceding process of embalming.
Gall Bladder is the reservoir of the bile; it is a sac situated in a fosse on the under surface of the right lobe of the liver.
Pancreas.—It is a long, flattened, conglomerate gland; it is about six inches in length, and is situated transversely across the posterior wall of the abdomen and behind the stomach.
Supra-Renal Capsules are two small, yellowish and flattened bodies surmounting the kidneys, and inclining inwards and towards the vertebral column.
Kidneys are the secreting organs of the urine; they are situated in the lumbar region, and at each side of the vertebral column.
Pelvis.—The cavity of the pelvis is that portion of the great abdominal cavity which is included between the bones of the pelvis. The viscera of the pelvis in the male are the urinary bladder, prostrate gland and rectum.