PATHOGENIC MICROORGANISMS. 213 



In what two forms is it found in the blood ? 



For what animals is it pathogenic? 



May blood of relapsing fever give rise to other cases of the disease by 

 inoculation? 



Does one attack of relapsing fever confer immunity upon the subject ? 



What is the Spirochseta or Treponema pallida ? Its morphology and 

 staining? 



What is the Spirochseta refringeus? 



How distinguished from the pallida? 



What is Levaditi's method for staining the Spirocbseta pallida in tissues ? 

 Pathogenesis of spirochaeta pallida ? 



Describe the Wassermann test in syphilis. Noguchi's modification. 



Describe the spirochsete of yaws. 



What is Vincent's angina ? 



Describe the Spirochseta gallinarum. 



What is Spirochseta anserhm>? 



CHAPTER XXIV. 



THE PATHOGENIC MICROORGANISMS OTHER THAN 

 BACTERIA. 



ACTINOMYCOSIS, MALARIA, AND AMOEBIC COLITIS. 



Streptothrix. 



THE streptothrix group, which has not as yet been clearly 

 defined, presents a number of varieties which have been 

 found pathogenic. This group of microorganisms resembles 

 the bacteria, yet differ from them in a number of important 

 respects, and are associated, on the other hand, with the 

 moulds. They resemble the moulds in so far that they develop 

 from spore-like bodies into dichotomously branching threads, 

 which grow into colonies having more or less the appearance 

 of true myeelia. Under favorable conditions some of the 

 threads become fruit hypha3 and break up into a number of 

 spore-like bodies. These sporiform bodies differ from bac- 

 terial spores in the fact that they are stained by the ordinary 

 method of staining. They resemble the bacteria in the fact 



