. Text-book of normal histology: including an account of the development of the tissues and of the organs. are identical in structure, both consistingof dense arterial net-works surrounded by irregular groups ofgranular polyhedral cells, whose presence suggested the oncesupposed glandular nature of the organs. The entire plexiform massis invested by connective tissue, from which fibrous septa pene-trate between the vascular structures. Numerous non-medullatednerve-fibres are also present. The true nature and function of these rudimentary organs are en-tirely unknown, and probably will remain s
. Text-book of normal histology: including an account of the development of the tissues and of the organs. are identical in structure, both consistingof dense arterial net-works surrounded by irregular groups ofgranular polyhedral cells, whose presence suggested the oncesupposed glandular nature of the organs. The entire plexiform massis invested by connective tissue, from which fibrous septa pene-trate between the vascular structures. Numerous non-medullatednerve-fibres are also present. The true nature and function of these rudimentary organs are en-tirely unknown, and probably will remain so until the embryology ofthese bodies is better understood. THE LYMPHATIC SYSTEM. 115 CHAPTER VIII. THE LYMPHATIC SYSTEM. The lymphatic system consists of two parts—the lymph-channelsand their contents the lymph, and the lymphatic tissue. Theformer may be represented by irregular interfascicular clefts betweenthe bundles of fibrous tissue or by vessels with well-defined walls,while the latter may exist as diffuse adenoid tissue, the simple lym-phatic nodule, or the complicated compound THE LYMPH-CHANNELS. The lymphatic spaces, the radicles of the more distinct vessels,are almost universally present, since they exist in almost everylocality where connective tissue abounds, forming intercommuni-cating systems of greater or less perfection throughout the Fig. 135. various organs. The relationbetween the connective tissueand the lymph-radicles is veryintimate, and it may be assumedthat all mterfascicidar cleftsare directly or indirectly con-nected with the lymphatics. Inloose areolar tissues, as the sub-cutaneous, the lymph-spacesare ill-defined clefts, irregularin form and size, which arebounded by the neighboring bundles of fibrous tissue and hned by an imperfect layer of endo-thelioid connective-tissue cells. In the denser forms of fibroustissue, as the central tendon of the diaphragm, cornea, etc., thelymph-spaces are more limited and form well-defined intercomm
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