272 LABOR A TOR Y GUIDE IN PHYSJOLOG Y. 



(a) If there is a variation is there any periodicity to 



be observed ? 

 (/$) Seek for causes of any variations in the same 



apparently normal individual. 



(4) The volume per cent as recorded by the haematocrit 

 varies with the product of two factors ; the average 

 volume of the individual corpuscles multiplied by the 

 number of corpuscles per unit volume. (V x v X n) 

 (#) Is the average volume of the individual corpus- 

 cles (v) necessarily constant? 



() If it is not constant, would one be justified in 

 drawing conclusions regarding the number of cor- 

 puscles per unit volume (n) after observing the 

 volume per cent (V) with the haematocrit? 



(5) What variation of the observation as above made 

 would enable one to determine with reasonable accu- 

 racy the number of corpuscles per cubic millimeter ? 



