392 SPIRILLA, PATHOGENIC VIBRIONES, SPIROCHETE 



11. What are the characteristic cultural differences between the vibriones 

 of Asiatic cholera and of Metchnikoff? 



12. What is the test for the presence of nitrites and indol in culture media? 



13. Name and describe some other non-pathogenic vibriones. 



14. What was the first pathogenic spirocheta discovered? What disease does 

 it produce? How is this disease spread? 



15. What is the cause of .African tick fever. How is it spread? 



16. Describe the morphology, staining, and cultural properties of Spirocheta 

 pallida. 



17. In what disease is it found? How can its presence best be demonstrated? 



18. Describe some diseases caused by spirocheta in domestic birds. How are 

 those diseases spread? 



19. State in what mammals spirochete have been found and what is known 

 about their pathogenesis. 



20. Discuss the question whether spirochete are protozoa and near relatives 

 of trypanosomes or not. 





