IV 



CHAPTER XXXI PAGE 



The Spirochaetae. Relapsing fever - 375 



CHAPTER XXXII 

 Yellow fever. Stegomyia calopus 384 



CHAPTER XXXIII 

 Blood-sucking flies. Tsetse flies, etc. 386 



CHAPTER XXXIV 

 Fixatives. Stains. Weights and measures. Apparatus. 404 



