140 INFECTIOUS DISEASES DUE TO PROTOZOA 



not generally found on microscopical examination. When not 

 found on microscopical examination the injection of blood into 

 susceptible animals (horses, dogs, mice, rats) proves their ex- 

 istence. 



Fig. 19. 



Trypanosoma equiperdum, blood, mice; a, four days after inoculation, 

 b, eight days after inoculation (Rouget). 



Changes in the blood. — There is a progressive diminution in 

 the Dumber of red corpuscles and in the amount of hemoglobin. 

 The red corpuscles may fall to 3,000,000 or less some days before 

 death. Voges found them reduced to 800,000 in one case. The 

 hemoglobin may be reduced to five or six per cent, (grams per 

 100 cc). The leucocytes appear to be increased. Sivori and 

 Lecler found 10,000 on the fourth day after inoculation. Of these 



