ALTERATION OF CELLULAR ELEMENTS OF MATRIX. 79 



peritonitis in consequence of starch-injection into the peritoneum, 

 many of the straight lymphatic capillaries of whose centrum tendineum 

 were plugged up by lymph-corpuscles. 



As regards the peri- and endo-lymphangial nodules and cords of 

 the omentum, it is to be noticed that in chronic inflammation a very 

 active proliferation of the elements of those structures takes place. 

 The best example to ascertain this fact is to be found in the omentum 

 of guinea-pigs in different stages of the tuberculous process. Here 

 it can be shown that those structures increase not only in size, but, 

 what is of greater importance, also in number. Not only the branched 

 cells of the matrix, but also the lymphoid corpuscles that are in direct 

 or indirect connection with it, undergo very active proliferation. The 

 branched cells of the matrix become very much more abundant by 

 growing into the neighbouring tissue ; they are first large in their 

 body as well as in their processes, but gradually become transformed 

 into a delicate reticulum. It is very common to find such branched 

 cells of the matrix whose body is provided with a number of small 

 constricted nuclei, and amongst the lymphoid corpuscles of the 

 matrix, multinuclear large elements are oftener to be met with than 

 in the normal condition. 



By the out-growth of the branched cells of the matrix very often 

 secondary nodules and cords are formed, which in some instances pro- 

 ject over the general surface of the omentum like bridges, villi or 

 papillae ; they are, as has been stated previously, more or less covered 

 with germinating endothelium. 



After having discovered the pseudo-stomata on the omentum, my 

 attention was directed to the question, whether in chronic inflamma- 

 tion the proliferation of the protoplasmic elements representing the 

 pseudo-stomata plays any part in the development of those smaller 

 and larger villous projections that are so often to be found on the 

 omentum as well as on other portions of the peritoneum. 



It was soon ascertained that the pseudo-stomata do not only pro- 

 liferate in the way above stated, viz. budding lymphoid cells to the sur- 

 face, which resemble young endothelial elements, but also that they 

 grow out over the general surface as protoplasmic masses, which 

 carry with them the surrounding zone of the endothelial cells. As 



