50 Veterinary Medicine. 



pigs from the same market, is significant in this respect. It is 

 further significant that the hog cholera bacillus is a very protean 

 microbe. Th. Smith, to whom we owe more than to any one 

 else the identification of the germ, gives seven varieties, which 

 showed well-marked distinctions in their morphology, in their 

 modes of growth on culture media, in the amount of gas they 

 respectively produced in a glucose bouillon, or in their patho- 

 genesis for rabbits. One of these modified germs which has 

 largely parted with its virulence for pigs and some other animals, 

 may under specially favorable conditions, resume its former po- 

 tency and proceed on a new career of infection. 



Lesions in the Acute or Septicizmic Form. The skin and sub- 

 cutaneous fat are the seats of diffuse blotches or spots of a deep red 

 varying from dark purple to light red, confined it may be to the 

 inner sides of the arms and thighs, the belly, the ears, eyelids, and 

 muzzle, or it may be all but uniformly diffused over the body. 

 When pressed so as to expel the blood, the greater part of the 

 surface may be momentarily whitened, but red points remain 

 representing the minute extravasations. Under the microscope 

 the red points show tortuous and enlarged capillaries with here 

 and there a rupture and minute clot. The visible mucosae may 

 show similiar petechiae, as may also the serosse of the chest, cra- 

 nium and abdomen. In the latter, blood extravasations are liable 

 to be more extensive. The spleen and lymph glands ( particu- 

 larly those of the bowels and omentum, the sublumbar and sub- 

 dorsal regions ) are usually enlarged, gorged with blood and 

 softened. Many of the lymph glands may escape, and in others 

 the congestion is largely confined to the cortical portion. The 

 lungs may show petechiae and even extensive haemorrhages into 

 their substance. The kidneys may show petechiae in the glome- 

 ruli, the medullary substance, the papillae or the pelvic mucosa, 

 or there may be larger circumscribed haemorrhages. 



The stomach in its greater curvature especially is usually 

 deeply congested and petechiated, with small submucous extrava- 

 sations, and these conditions are liable to be still more marked in 

 the small intestines and especially in the large, which may have a 

 dark red or port wine hue. Blood may be present in clots among 

 the contents. Necrotic ulcers are absent. 



Lesions in the Protracted and Chronic Forms. The lesions of 

 the skin are usually less, extensive than in the acute type, and 

 may be almost entirely absent. The lymph glands are enlarged 



