Parasitic Protozoa. 161 



are invariably present when the chills occur and are found 

 only at this time. 



There may, however, be but one variety and the irregular 

 recurring chills or their frequency be due to the invasion 

 of the system at the same time of the organisms indifferent 

 stages of development and which in consequence segmented 

 on successive days. This remains, however, to be proven- 

 That this organism belongs to the Protozoa and that it will 

 and does account for all the morbid processes present seems 

 now to he undoubted. It produces a more or less rapid 

 destruction of the red cells with a consequent anaemia and 

 abnormal discharge of pigment resulting from their des 

 truction. This pigment is in part eliminated by the kid- 

 neys, and in part by the liver in the cells of which large 

 quantities are invariably present. But what is its form, or 

 how does it develop apart from the human body ? 



Malaria is found in low , marshy regions characterized by 

 a luxuriant vegetation,, along low sea coasts, estuaries or 

 the banks of sluggish streams, in temperate as well as 

 tropical climes. Moisture seems to be particularly favorable 

 to its development as it seems more active in spring and 

 autumn. In those districts where at one time malaria 

 was very common, but which, have since been drained and 

 cultivated it has almost disappeared. It has not, however, 

 been discovered in the water or soil of these districts and 

 its mode of life there is as yet a mere matter of speculation. 



The other condition referred to as probably due to a 

 species of Protozoa is cancer. There is no condition more 

 universal, more fatal, and more dreaded than this, and for 

 ages some of the greatest thinkers have attempted to give 

 a rational explanation for its aetiology and its treatment. 

 Unfortunately as yet surgery is the only effective remedy 

 known and then only in its primary stages. Theory after 

 theory has been advanced to explain its cause, heredity, 

 irritation, embryological cell disturbances, etc., but it is 

 only very recently that a plausible explanation has been 

 given, and tl is seems to be the result of the labor of several 

 pathologists who have all reached the same conclusion. 



