582 THE TISSUES. 



Deposits of pigment occur as a consequence of hepatization, or 

 from a simple congestion of the lungs. Tubercle (gray granula- 

 tions) is most frequently deposited in the air-cells (Fig. 408); cancer, 

 in the interstitial tissue. The former is liable to cretaceous trans- 

 formation (Fig. 409). 



4. In oedema of the lung, serum is effused into the air-cells; in 

 apoplexy, blood is extravasated into the interstitial tissue. 



5. The epithelial cells undergo a fatty degeneration in portions of 

 the lung encompassed by a pleuritic effusion, in atelectasis (Rein- 

 hardt), and in splenization. 



6. New formations (bone and cartilage), and cysts, are generally 

 noticed in the interstitial tissue. 



7. The parenchyma of the lung is destroyed by inflammation, 

 gangrene, tubercle, or cancer ; the elastic fibres usually being well 

 preserved, while the remaining elements are infiltrated with fine 

 fatty molecules. 



For the pathological states of the air-passages, reference may be 

 made to the works on pathological anatomy. 



CHAPTER XVII. 



THE BLOOD-VASCULAK GLANDS. 



THIS class includes a series of organs possessing a glandular 

 structure, but no excretory ducts ; and which are supposed to ela- 

 borate substances from the blood to be again applied to some pur- 

 pose in the organism, after resorption from their tissue. As they 

 derive their designation from a mere hypothesis, it were doubtless 

 better to abolish it altogether. "Ductless glands" (Todd and 

 Bowman) is a better designation. 



The following organs are referred at the present time to this class; 

 all of which have been described in connection with other parts 

 and organs, except the last four. 



The anterior lobe of the pituitary body (p. 465); the solitary 

 follicles of the stomach and intestine, and the aggregated follicles of 

 the small intestine (p. 530); the follicular glands in the root of the 

 tongue, the tonsils, and the pharyngeal follicles (p. 573), and the 

 lymphatic glands (p. 510). 



The spleen, the thyroid body, the thymus, and the supra-renal 

 glands still remain to be described. 



