RHINOSCLEROMA. 227 



On agar-agar the growth first develops as small very 

 dry discrete irregular masses that tend to become confluent 

 and develop a yellow color. On blood-serum the growth 

 is not so luxuriant as on agar, but has the same formation 

 and appearance. Similar appearing masses are developed in 

 bouillon, some of them floating on the surface of the medium 

 and others sinking to the bottom. Milk is not coagulated, 

 nor is its reaction changed. On potato large dry scales of a 

 pale-yellow color are formed. 



Injection into animals of a pure culture of the streptothrix 

 produces the disease, thus positively establishing its etiology. 

 The horse, dog, ass, and rabbit are immune. Intraperitoneal 

 injection into susceptible animals is followed by extensive 

 development of little tubercles in the omen turn and the peri- 

 toneal covering of the abdominal viscera. Intravenous 

 injection is followed by the development of tubercles in all 

 parts of the body, resembling an acute miliary tuberculosis. 



Rhinoscler oma . 



This disease is characterized by the development of small 

 circumscribed tumors on the nasal mucous membrane. From 

 this point the disease gradually spreads to the surrounding tis- 

 sues, sometimes as far as the pharynx. The tumors resemble 

 the lesions of glanders, but do not ulcerate. 



Yon Frisch discovered an organism in the lesions which 

 resembles Friedlaender's pneumobacillus in every particular. 

 It is surrounded by a capsule, stains readily by Gram's 

 method, and is always found within the tissue-cells. It grows 

 readily on all the various culture-media and induces fermen- 

 tation of sugar. Milk is coagulated. It has been impossible 

 to produce the disease in animals by inoculation, 



