COCCIDIUM 231 



toes oil should be poured on the water, thus cutting off the air and 

 means of respiration. 



Boss, of New Orleans, claims to have successfully cultivated 

 malarial plasmodia of the species, vivax and falciparum by the use 

 of human blood. He has also succeeded when using Locke's fluid 

 minus calcium chloride plus ascitic fluid. One-half percent dex- 

 trose is usually added. The blood is drawn, so that it can be 

 defibrinated, into small flat bottom tubes. These are incubated at 

 40 C. The column of fluid is 1-2 inches high, the clear serum layer 

 being 1/2 inch at least. The parasites grow in the upper layer of 

 the cellular sediment. Undiluted serum and leucocytes are lytic 

 for plasmodia. For renewed cultures these must be removed but 

 uninjured red cells must be added. Only the asexual division has 

 been observed. Leucocytes phagocyte all free parasites under 

 artificial conditions. 



COCCIDIUM. 



Coccidium hominis is another member of the sporozoa that occa- 

 sionally infects man. Coccidia are infectious also for horses, goats, 

 oxen, sheep, pigs, guinea pigs, weasels and rabbits. The organism 

 is essentially a cell parasite inhabiting the cells of the gastrointes- 

 tinal tract by preference, chiefly the liver and intestinal mucous mem- 

 branes. They lead a sexual and asexual existence like the malarial 

 parasites (alternate generation) . The young sickle-shaped nucleated 

 sporozoite penetrates an epithelial cell, where it gradually 

 develops, ultimately dividing into numerous sporozoites. This is the 

 asexual stage of development (schizogony) , the sexual stage being 

 called sporogony. 



The sporozoites are differentiated into the two sex elements. 

 These are large granular appearing cells, the male being smaller, 

 divides into numerous flagellated microgametes that penetrate the 

 female granular cells, macrogametes, and fertilize them. These 

 fertilized macrogametes, or zygotes form capsules and become 



