INTRAPERITONEAL INOCULATION. 41 



Stain the sections of diphtheria membrane furnished. 



(a) By Gram's or Weigert's method, counterstain- 

 ing with eosin. 



Carry through the staining processes on the slide. 



(6) In Czinzinski's solution, 



Alcoholic eosin — .5% solution in 70% alcohol 20 cc. 



Saturated aqueous solution, methylene blue 40 cc. 



Water 40 cc. 



"Place the sections in this stain for 6 to 24 hours. 

 Wash thoroughly in water till all blue color is removed, 

 that will come away. Dehydrate in absolute alcohol, 

 clear in xylol and mount in usual manner. 



Intraperitoneal Inoculation of Guinea Pigs. 

 (Class Demonstration.) 



A medium sized guinea pig is chosen. The hair is 

 removed from the median line of abdomen and the skin 

 is washed with 1 in 1000 bichloride of mercury solution. 

 With a sterilized hypodermic syringe .5 cc. of a 24 

 hour broth culture of moderately virulent Spirillum 

 cholerae asiaticae is thrown into abdomen, the needle 

 being entered about the centre of the mid-line. The 

 animal usually dies in from 18 to 36 hours. 



