PLASMODIUM MALARIA. 627 
There is still much uncertainty with regard to the 
slassification of the parasites. Many authors place them 
among the sporozoa in the order of the hemosporidia of 
Danilewsky; others place them in the sarcodinia, and 
speak of them as hemamebe. Until the matter is settled, 
however, they may be considered to belong to the gen- 
eral order of protozoa and to that group of organisms 
known as heematozoa. Parasites of the red blood-cor- 
puscles have been met with abundantly in the blood of 
fish, turtles, and many species of birds. 
The relation of the different forms of the malarial 
parasite to each other and to the varieties of the disease 
are still under discussion. Galgi, Marchiafava and 
other Italian observers hold that they are distinct 
varieties, not interchangeable, though closely allied 
biologically. Laveran, on the other hand, contends for 
the unity of the forms, which he regards as modifica- 
tions of one polymorphic parasite. But with the 
present imperfect knowledge of the full life-history of 
the parasite the question cannot be considered as settled. 
The following varieties are associated with the differ- 
ent forms of malarial fever : 
I. Parasite of the Simple Intermittent Fever. (a) TER- 
TIAN ParasiTE (see Plate II.). If the blood of a 
patient be examined during or shortly after the chill 
in tertian fever, inside the red blood-corpuscles, or less 
often free in the plasma, will be seen small, pale, hya- 
line amoebee which undergo rapid changes in shape, 
often assuming the form of a star or of a cross. There 
may be no pigment visible, and to these hyaline bodies 
Marchiafava and Celli gave the name plasmodia. Ina 
few examples scattered pigment granules may be seen 
in the ameebe, usually placed near the periphery. In 
