EPITHELIAL AND ENDOTHELIAL TISSUE. 



351 



The myxomatous reticulum of the pulp-cords of the spleen 

 contains in its meshes lymph-corpuscles in different stages of 

 development and multinuclear bioplasson masses ; also a varying 

 number of pigment granules, either scattered in the lymph-cor- 

 puscles or grouped in the shape of dark brown pigment clusters. 

 In accordance with the view that red blood-corpuscles originate 

 in lymph-corpuscles, almost all observers describe lymph-cor- 

 puscles as containing colored blood-corpuscles ; others maintain 

 the origin of these corpuscles from the endothelia. Such views, 

 however, are erroneous, and Johnstone has demonstrated the 



FIG. 148. FOLLICLE OF THE SPLEEN OF A BADGER, IN CONNECTION 

 WITH AN ARTERY. 



L, lymph-follicle ; A, artery, penetrating the follicle ; Ad, adventLtial coat of the artery, 

 crowded with lymph-corpuscles ; M, muscle-strings of the spleen, accompanying the artery ; 

 V, blood- and lymph- vessels in transverse section ; P, clusters of pigment in the tissue of the 

 spleen. Magnified 500 diameters. 



source from which the colored blood-corpuscles arise, both in the 

 lymph-ganglia and in the spleen here, especially, in large num- 

 bers. (See page 105.) The significance of the multinuclear 

 bodies is unknown, and there is no reason to term them the 

 graves of the colored blood-corpuscles. 



The arteries send numerous branches into the adventitial 

 lymph-tissue and the lymph-follicles ; they finally divide into 



