646 INFECTION AND IMMUNITY. 



In addition to the European relapsing fever 

 there are at least three recurrent fevers caused by 

 varieties of spirilla distinct from one another in 

 morphology and according to Kolle and Schatiloff 

 in complement deviation. One of these three 

 forms occurs in India. The other two are known 

 as African tick fever. Of these two forms, that 

 of West Africa was studied by Button and Todd. 

 The other form is prevalent in East Africa and 

 was studied by E. Koch. According to Koch, the 

 ticks which carry the organisms also transmit 

 them to the eggs, which in turn develop into ticks 

 capable of infecting man. Koch found spirilla in 

 only a part of the eggs of infected ticks. 



II. SYPHILIS. 



Historical it is impossible here to describe or even men- 

 tion the many cocci, bacteria and protozoa (?) 

 which have been brought into etiologic relation- 

 ship with syphilis. Until recently, the bacillus of 

 Lustgarten occupied a fairly prominent position 

 as the possible cause. This organism resembles 

 the tubercle bacillus in its morphology and stain- 

 ing properties, and is not to be differentiated from 

 one of the smegma bacilli. Its recognition in 

 syphilitic lesions has always been difficult, and by 

 far the greatest number of investigators have been 

 unable to demonstrate it. It has never received 

 general recognition as the cause of the disease, and 

 its presence in lesions of the genitals has no sig- 

 nificance because of the occurrence of smegma bac- 

 illi in this locality. 



The bacillus of De Lisle and Julien, and that 

 of Joseph and Piorkowski rest on no better basis. 



