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HAND-BOOK OF PHYSIOLOGY. 



prolonged from the inner surface of the part of the capsule covering the 

 convex or outer part of the gland; they have a structure similar to that 

 of the capsule, and entering the gland from all sides, and freely commu- 

 nicating, form a fibrous supporting stroma. The interior of the gland 

 is seen on section, even when examined with the naked eye, to be made 

 up of two parts, an outer or cortical (Fig. 212, c, c), which is light- 

 colored, and an inner of redder appearance, the medullary portion (Fig. 

 212). In the outer or cortical part of the gland (Fig. 215, c) the inter- 

 vals between the trabeculse are comparatively large and more or less trian- 



FIG. 212. 



FIG. 213. 



FIG. 212. Section of a mesenteric gland f rom the ox, slightly magnified, a, Hilus; b (in the cen- 

 tral part of the figure), medullary substance; c, cortical substance with indistinct alveoli; d, capsule 

 (Kolliker.) 



FIG. 213. From a vertical section through the capsule, cortical sinus and peripheral portion of 

 follicle of a human compound lymphatic gland. The section had been shaken, so as to get rid of most 

 of the lymph corpuscles. A. Outer stratum of capsule, consisting of bundles of fibrous tissue cut at 

 various angles. B. Inner stratum, showing fibres of connective tissue with nuclei of flattened con- 

 nective-tissue-corpuscles. Beneath this (between B and C) is the lymph-sinus or lymph-path, contain- 

 ing a reticulum coated by flat nucleated endothelial cells. C. Fine nucleated endothelial membrane, 

 marking boundary of the lymph-follicle. The rest of the section from C to E is the adenoid tissue of 

 the lymph-follicle, which consists of a fine reticulum, E, with numerous lymph-corpuscles, D. They 

 are so closely packed that the adenoid reticulum is invisible till the section has been shaken so as to 

 dislodge a number of the lymph-corpuscles, x 350. (Klein and Isoble Smith.) 



gular, the intercommunicating spaces being termed alveoli; whilst in the 

 more central or medullary part a finer mesh work is formed by the more 

 free anastomosis of the trabecular processes. In the alveoli of the cortex 

 and in the mesh work formed by the trabeculae in the medulla, is contained 

 the proper gland structure. In the former it is arranged as follows (Fig. 

 215): occupying the central and chief part of each alveolus, is a more or 

 less wedge-shaped mass (l.h.) of adenoid tissue, densely packed with lymph 

 corpuscles; but at the periphery surrounding the central portion and im- 

 mediately next the capsule and trabeculaa, is a more open meshwork of 

 adenoid tissue constituting the lymph sinus or channel (Is.), and contain- 



