DISTRIBUTION OF BACILLI. 439 



bubonic form is the affection of the lymphatic glands, 



which undergo intense inflammatory swelling, attended with 



haemorrhage, and generally ending in a greater or less 



degree of necrotic softening if the patient lives long enough. 



The connective tissue around the glands is similarly 



affected. True suppuration is rare. Usually one group of 



glands is affected first, constituting the primary bubo in 



the great majority the inguinal or the axillary glands and 



afterwards other groups may become involved, though to a 



much less extent. Along with these changes there is great 



swelling of the spleen, and often intense cloudy swelling of 



the cells of the kidneys, liver, and other organs. There may 



also occur secondary areas of haemorrhage and necrosis, 



chiefly in the lungs, liver, and spleen. The bacilli occur 



in enormous numbers in the swollen glands, being often so 



numerous that a film preparation made from a scraping 



almost resembles a pure culture ; they lie irregularly 



arranged between the cellular elements. In the spleen 



they are fairly numerous, and in the secondary lesions 



mentioned they are often abundant. In the pulmonary 



form the lesion is the well-recognised "plague pneumonia." 



This is of broncho-pneumonic type, though large areas may 



be formed by confluence of the consolidated patches, and 



the inflammatory process is attended usually by much 



haemorrhage ; the bronchial glands show inflammatory 



swelling. Clinically there may be little or no cough or 



expectoration ; in the sputum the bacilli may be found in 



large numbers. The disease in this form is said to be 



invariably fatal. In the septicaemic form there is no 



primary bubo discoverable, though there may be a general 



enlargement of lymphatic glands ; here also the disease is 



of specially grave character. An intestinal form with 



extensive affection of the mesenteric glands has been 



described, but it is exceedingly rare so much so that 



many observers with extensive experience have doubted its 



occurrence. In the various forms of the disease the 



bacilli occur also in the blood, in which they may be 



found during life by microscopic examination, chiefly, how- 



