INDEX. 



497 



Whey, Petruschky's, 136 

 Whooping-cough, 476 

 bacillus of, 476, 477 

 bacillus Xin, 477 

 Widal serum-test for typhoid fever, 



382, 383 

 Wolfhiigel's apparatus for count- 



ing colonies of bacteria upon 



plates, 169 

 Wooden tongue, 265 

 Wounds, unprotected, entrance of 



bacteria into, 62 



, effects of, on growth of 

 bacteria, 49 



YEAST-PLANT as the cause of fer- 

 mentation, discovery of, 27 

 32 



Yellow fever, 399 



antitoxic serum of, 408 

 bacillus of, 400. See Bacillus 



icteroides. 



coli communis in, 399, 400 

 bacillus X in, 400 

 cause of black vomit in, 404 

 causes of death in, 403 

 Havelburg's bacillus in, 405 

 pathology of, 405 



ZIEHL'S method of demonstrating 

 the presence of tubercle ba- 

 cilli in sputum, 213 



Zooglea, 148 



Zoph's classification of the bacteria, 



4i 

 Zymogenic bacteria, 50 



