LYMPHATICS, the vessels containing the lymph (q.v.), are also called absorbents, from the property which these vessels possess of absorbing foreign matters into the system, and carrying them into the circulation. The lymphatic system includes riot only the lymphatic vessels and the glands through which they pass, but also the lacteals (q.v.), which are nothing more than the lymphatics of the small intestine, and only differ from. other lymphatics in conveying chyle (q.v.) instead of lymph during the latter part of the digestive process.
The lymphatics are minute, delicate, and transparent vessels, of tolerable uniformity in size, and remarkable for their knotted appearance, which is due to the presence of numerous valves, for their frequent dichotomous divisions, and for their division into several branches before entering a gland. They collect the products of digestion and the products of worn-out tissues, and convey them into the venous circulation near the heart. They are found in nearly every texture and organ of the body, excepting the substance of the brain and spinal cord, the eyeball, cartilage, tendon, and certain fetal strictures, and possibly. also the substance of bone.
The lymphatics are arranged in a superficial and a deep set. The superficial vessels on the surface of the body lie immediately beneath the skin, and join the deep lymph atics in certain points through petforations of the deep fascia; while in the interior of the body they lie in the sub-mucous and sub-serous areolar tissue. They arise in the form
of a net-work, from which they pass to lymphatic glands or to a larger trunk. The deep lymphatics are larger than the .superficial. and accompany the deep blood-vessels; their mode of origin is not known with certainty. The structure of the lymphatics is similar to that of veins and arteries.
The lyntphatic or absorbent glands are small, solid, glandular bodies, varying from the size of a liernp-seed to that of an almond, and situated in the course of the lymphatic vessels. They are found in the neck (where they often become enlarged and intlained, especially in scrofulous subjects), in the axilla, or arm-pit, in the groin (where, when inflamed, they give rise to the condition known as bubo), and in the ham; while deep ones are found abundantly in the abdomen and the chest.
The lymph of the left side of trunk, of both legs, of the left arm, and the whole of the chyle, is conveyed into the blood by the thoracic duet (q.v.); while the lymph of the right sale of the head, neck, and trunk, and of the right arm, enters the circulation at the junction of the axillary anti internal jugular veins on the right side, by a short truuk, guarded at its opening by valves.