BACTERIAL DISEASES OF THE ANIMAL KINGDOM 125 



other respects, viz. in being slightly curved and in its staining 

 characteristics. The disease is, fortunately, not easily incurred by the 

 human subject, and not at all by the lower animals. A criminal 

 in the Sandwich Islands was inoculated in several parts of his 

 body with leprous tissue, and died from its effect several years later, 

 but in several other experiments negative results only have been 

 obtained. The method by which the disease is carried from one 

 person to another is still a controversial matter. Some maintain that 

 it is hereditary, but it is known that leprous subjects can bear 

 children free from the disease. On the other hand, the case of 

 Father Damien, who contracted the disease after going to the 

 Sandwich Islands, shows that it must be partly infectious. We may, 

 therefore, conclude that whilst the disease is infectious, its con- 

 tagiousness is of a low order, and it is probably hereditary, only to 

 this extent, that some people are more liable than others to catch the 

 disease, owing to the peculiarity of their organisation, which renders 

 their bodies a good nutritive medium for these bacteria. 



We come now to a bacterial disease caused by an organism 

 which belongs to the Spirillaceae. This is Spirillum Obermeieri, or 

 Spirochaete Obermeieri, as it should more properly be called. The 

 disease for which it is responsible is called Kelapsing Fever. As seen 

 in Fig. 78, this organism is like a corkscrew in shape. In the blood, 

 during fever, the spiral may be from 

 two to six times the diameter of a \^/^^\„^\^^^^^ 



blood corpuscle. Obermeier found Fig. 78.-Spirillum obermeieri. 



that the microbe disappeared about 



the time of the crisis of the fever, and reappeared again when a 

 relapse occurred. The disease has been experimentally communicated 

 by inoculation to man and to apes. The spirals are actively motile, 

 and move in the manner peculiar to organisms of this kind, namely, a 

 forward accompanied by an undulatory movement. The individuals 

 of this organism are found throughout the whole body, and are not 

 confined to local areas. A cultivation in a pure state has not yet been 

 achieved, so that very little, either of it or of its toxin, is at present 

 known. 



The term Pneumonia is applied to several kinds of illnesses, but all 

 are varieties of lung inflammations, in which modifications are 

 produced depending on the special structure of the lung or of the 

 parts of it which are affected. Two bacteria are associated with this 

 disease, viz. Fraenkel's pneumococcus and Friedlander's pneumo- 

 bacillus. 



