508 



THE RESPIRATOKY SYSTEM. 



FIG. 288. AN OLD FIBROUS TUBERCLE OF THE LUNG "HEALED TUBERCLE." 



The central portion is necrotic and irregularly pigmented. The periphery is composed of dense pigmented 

 fibrous tissue. There are emphysema and distortion from cicatricial contraction of the fibrous tissue. 



PIG. 289. A FIBROUS TUBERCLE "HEALED TUBERCLE" OF THE LUNG. 



The centre Is caseous, the fibrous tissue surrounding this is dense, the walls of the surrounding air spaces 

 are thickened. A giant cell at the right ie calcified. 



