ALTERATION OF CELLULAR ELEMENTS OF MATRIX. 77 



made out, especially of small finely-granular cells, which may be 

 taken in all probability as emigrated colourless blood corpuscles. 



In lymphatic nodules which lie in the neighbourhood of a vessel, 

 and which possess either a scanty system of vessels or even none 

 whatever, and which, according to the description given in Section I., 

 are to be regarded as being in an early stage of development, we are 

 likely to find a number of the lymph-canalicular cells which possess 

 on their body or on a process, buds of various sizes in such a number 

 as is not to be found in the uninflamed state ; the condition of their 

 nucleus is usually that of division, sometimes it is divided into two 

 or three small nuclei. From these appearances we may conclude 

 that here also an active inflammatory change had taken place. 



Of the greatest importance as regards the changes of the branched 

 cells of the lymph-canalicular system of the mesentery and omentum 

 of the guinea-pig and dog was the examination of these membranes 

 in the osdematous condition during the second or third day of the 

 inflammation. If, after what I had seen on the centrum tendineura 

 and omentum of the rabbit, I had had still any doubt about the 

 active participation of the cells of the lymph-canalicular system in 

 the production of young cells, the study of the oedematous mesentery 

 of those animals just mentioned would have cleared up completely 

 every doubt. 



(b.) Chronic Inflammation. The most important changes in 

 branched cells of the lymph-canalicular system occur in chronic in- 

 flammation, which may arise from the most various causes. We will 

 commence with the centrum tendineum. 



Centrum Tendineum. If we prepare a centrum tendineum of a 

 guinea-pig which has tubercular nodules on the centrum tendineum, 

 by pencilling its pleural surface and subsequent staining with silver 

 solution, we shall obtain a satisfactory understanding of the changes 

 of the cells of the lymph-canalicular system if the preparation is a 

 successful one, that is, if the system of lymphatic vessels and lymph 

 canals is plainly and beaiitifully to be seen. Besides places where 

 the lymphatic vessels and the system of lymph-canals, as well as the 

 cells of these, present no deviation from the normal condition, there 

 are spots to be met with where a distinct change has occurred, the 



