196 EXAMINATIONS OF WATER, AIR, AND SOIL. 



What is meant by the double-tertian and double-quartan forms of mala- 

 rial fever? 



To what is the quotodian form of fever due? 



Give the techuic for the examination of fresh malarial blood for diag- 

 nostic purposes. 



How are stained specimens prepared for examination V 



What is the differentiation between the quartan and tertian parasite in 

 the blood ? 



Is the blood of malarial patients infectious ? 



Amoeba Coli. 



Where is the Amceba coli found? To what kingdom does it belong? 

 Describe it. 



What is the endoplasm ? 



What is the ectoplasm ? 



How is Amoeba coli stained? 



What may be seen in the bod y of the Amceba coli f 



What causes the motion of the amoeba? 



How is examination for the Amoeba coli practised ? 



CHAPTER XXIV. 



BACTERIOLOGICAL EXAMINATIONS OF WATER, AIR, 

 AND SOIL. 



THE BACTERIOLOGICAL INVESTIGATION OF WATER. 



BOTH qualitative and quantitative bacteriological examina- 

 tions of water are often resorted to in order to test the adapta- 

 bility of this substance for human and animal consumption. 

 By the quantitative test the number of bacteria present in 

 the water is ascertained without any reference to their patho- 

 genic character, and when this number exceeds 500 bacteria 

 per c.c. the water is condemned. This is evidently not a 

 very fair test, but it is not without value when it is consid- 

 ered that in a number of instances the virulence of some 

 pathogenic microorganisms is increased when they are inocu- 

 lated together with saprophytic germs ; and again, that the 



