No. 498] 



THE SPIROCHETES 



379 



as the cause of a lymphatic spirillosis; it stains like 

 Treponema pallidum. More extended investigation 

 alone will justify assign mi a dclinile place to such organ- 

 isms. Yet apparently the group of spirochetes produ- 

 cing relapsing fevers may justly be made an independent 

 genus, even though their morphological differentiation is 

 difficult. They constitute the newly created genus. 



Spiroschaudixxia Sambon 1907 

 Blood parasites only imperfectly known. In blood .of 

 vertebrate host, they appear as minute, wavy or spiral 

 threadlike bodies. With undulating membrane but no 

 flagella. Free stage alternates with intracellular resting 

 stage with parasite coiled up in host cell. Sporogony in 

 ticks. Stages have been demonstrated in ova, showing 

 the hereditary transmission of the infection. This is con- 

 trary to known facts regarding bacteria. Type species, 

 Spiroschaudinnia recurrentis. 



This genus is as yet not clearly differentiated from 

 Splrovhaia and may ultimately prove to be synonymous 

 with it. The presence of an intracellular stage and the 

 mode of infection through biting insects are the slender 

 basis on which it rests at present. 



In this genus Sambon has included two forms which 

 produce relapsing fevers in man. One is S. recurrentis 

 (Lebert 1874), better known by the synonym Spirillum 

 obermeieri Cohn 1875, which is the cause of the relapsing 

 fever common in Russia, the Balkan Peninsula, Turkey, 



entire world. Patton has shown that the parasite is 

 transmitted bv the common bedbug {Acanthia lectularia) 

 and possibly bv the body louse (Pediculus vestimenti), 

 although the evidence is not conclusive. The second 



is difficult to distinguish morphologically from the fore- 

 going, but is shown by experiment in animals to be dis- 

 tinct from it. According to Dutton and Todd the organ- 

 ism is transmitted by the tick, Ornithodoros moubata 



