The Practical Study of Malaria 
Chapter 1 
The Normal Constituents of the Blood 
N ORMAL blood should be carefully studied in 
fresh and stained specimens. 
I. Red Cells (or normocytes).—6-9 fi. In fresh 
films they show a very faint central pale area. The 
colour on staining with Romanowsky (p. 21) varies 
with the amount of washing ; generally it is greenish 
or bluish, or faint eosin ; with Leishman, Giemsa, 
etc., a deeper eosin colour. 
2. Platelets. —2-4Vary much in size and 
shape. They frequently occur in masses in wet films 
and if examined an hour or so after formation these 
masses exude colourless drops of secretion best seen in 
‘ vital staining 5 specimens (Ross). They stain bright 
crimson with Romanowsky and lie in clumps of from 
six to fifty. They do not shew the red, white, and 
blue of a well-stained parasite but stain diffusely 
crimson or blotchy violet (Fig. 2). 
3. Blood dust (or Haemaconiae). — Refractive 
granules, smaller than micrococci, at most i/x in 
diameter. They shew active motion (Brownian) in 
fresh films. They are probably granules escaped from 
leucocytes. 
