144 On the Lymphatic System of the Lungs, [Jan, 29, 



with granules is said to be filled with micrococci. Against that view, 

 however, it can be maintained, first, that there are a number of normal 

 tissues that appear after hardening to be just as regularly filled with 

 granules (e. g. the liver-cells of any liver hardened in spirit), and, secondly, 

 that the resistance of these granules to acids and alkalies after hardening 

 does not prove them to be micrococci.] 



Where the alveoli contain giant cells, the alveolar septa are very much 

 thickened, and are seen to consist of a tissue that contains branched 

 and spindle-shaped cells, the substance of which has more or less the 

 appearance of a fibrous tissue, their processes as well as their body 

 being slightly fibrillar. Between these there are very few lymphoid 

 corpuscles to be found. 



In a third series of lungs, which also in macroscopical aspect did not 

 differ from the former ones, it is seen that almost all the nodules contain 

 giant cells, corresponding to the alveolar spaces. These, however, have 

 undergone changes which are correctly described by Schiippel and others ; 

 viz. the giant cells give origin to a network of branched nucleated cells, as 

 well as to a few spherical nucleated elements that lie in its meshes. This 

 network grows at the expense of the giant cell, which undergoes prolife- 

 ration at the same time. We have here what is generally called a reticular 

 tubercle. From one giant cell a number of giant cells may take their 

 origin. 



The nearer to the centre of a nodule the giant cell lies, the more exten- 

 sively and quickly does a transformation of its substance take place. It 

 becomes converted into a very dense feltwork of fibrillar tissue, the 

 nuclei of which gradually disappear, while the tissue itself dies away, 

 becoming firm and hard, and finally resembling a granular substance, in 

 which fibrils can be made out very indistinctly. While the network of the 

 nucleated cells continues to grow at the expense of the giant cells, the 

 process of necrosis spreads gradually to the peripheral parts. In this 

 stage of the process the thickened interalveolar trabeculaB become also 

 assumed into, and identified with, the tissue that originated from the giant 

 cells. In the neighbourhood of the nodules there are very numerous 

 places where the interalveolar trabeculaB are thickened and contain nume- 

 rous young cells, the epithelium of the corresponding alveoli being, at the 

 same time, in a state of proliferation. In general the tubercular nodules 

 of both these latter series have the common character that the peripheral 

 zone of the tubercular nodule is a regular adenoid tissue, being composed 

 of a delicate reticulum which includes small lymphoid corpuscules ; this 

 adenoid tissue is in continuity with the tissue of the interalveolar 

 trabeculse above mentioned. In these stages of the tuberculous process, 

 we find numerous branches of large blood-vessels, in the immediate 

 neighbourhood of the nodules, provided with the same perivascular 

 cords of adenoid tissue as have been described in the tuberculous lung 

 of the guineapig. 



