216 STRONG, CROWELL, AND TEAGUE. 



mucous membrane just above the vocal cords in a few cases was 

 not so markedly hypersemic, but below them, in every instance, it 

 appeared of a bright-red color. Throughout the entire length 

 of the trachea the hypersemia was always more marked below 

 the vocal cords, whatever the condition above them was. This 

 hypersemic condition continued in every instance throughout 

 the trachea and bronchi, though it was sometimes less marked 

 in the smaller tubes which led to normal lobes of the lung. In 

 no case was there noticeable oedema of the glottis. In a single 

 instance, in which the epiglottis and surrounding structures 

 showed no injection, the hypersemia and injection of the vessels 

 did not begin until about 3 centimeters below the cords. In a 

 few cases there were small haemorrhages measuring several milli- 

 meters in diameter in the mucous membrane of the trachea. 

 Over the surface of the trachea a small quantity of blood-stained 

 serous exudate, sometimes frothy in character, was present. 

 There was always much oedema of the tissues surrounding the 

 lower portion of the trachea, and the lymphatic glands in this 

 region were swollen to a greater or less degree. In one instance 

 two of them measured as much as 3 centimeters long by 1^ wide. 

 (See Plate XI.) On cut section they were usually red or bluish 

 in color and showed many haemorrhages. The glands at the 

 bifurcation of the trachea were always greatly swollen, generally 

 anthracotic, and in all instances were of an almost black-red color 

 from resulting haemorrhages in the glandular substance. 



Histological examination of the tonsils. — The morphological 

 changes in the tonsils are not prominent. The majority of the 

 tonsils examined did show very marked congestion and in some 

 cedema was present. Small haemorrhages were noted in a few 

 cases. The crypts frequently contained mucus in which very 

 moderate numbers of pest bacilli were present. The epithelium 

 and follicles for the most part showed no change. Some of the 

 tonsils were the seat of old inflammatory changes which were 

 unrelated to the plague infection. One case showed very active 

 proliferation of the lymphoid follicles. This case showed very 

 few plague bacilli in the tonsil itself but the greatest numbers 

 observed were present in the blood contained within the vessels 

 of the tonsil. The majority showed very few bacilli at any 

 place in the tonsil. 



One showed very large numbers of pest bacilli in the crypts 

 and scattered throughout the parenchyma, without any definite 

 distribution, except that the follicles were practically free. 



Another case showed a remarkable apparent leucocytosis judg- 

 ing from the number of leucocytes in the blood within the vessels. 



