MASTIGOPHORA 755 



As both parasites are found in the antelope, the prophylaxis is the 

 same. Bruce 1 is of the opinion that rhodesiense and brucei are 

 identical. 



Schizotrypanum cruzi. This parasite, which differs from all 

 other trypanosomes, is the cause of a form of human trypanosomyasis 

 occurring in Brazil. It is transmitted by a bug, Conorhinus megistus, 

 in which the parasite passes part of its cycle of development. In the 

 human being, multiplication takes place in endothelial cells, lympho- 

 cytes and other parenchymatous cells of the viscera; and also in the 

 skeletal and heart muscles. While in 

 this stage the parasite has no flagel- 

 lum and resembles the leishmania; 

 only after escape into the blood does 

 it take on the trypanosome form. 



Guinea-pigs, rats, mice and mon- 

 keys are susceptible ; the bed-bug, FIG. 176. SCHIZOTRYPANUM CRUZI 

 cimex, is also capable of transmitting IN HUMAN BLOOD. (From Dof- 

 the disease ^ n a ^ ter Chagas. MacNeal, Path- 



x-vj -i. -i . ] -i /^r, ogsnic JVlicroorganisms." pub- 



Cultures were obtained, by Onagas TIJU -n '-m i A > o 



J & lished by P. Blakiston s Sons & 



and proved virulent for animals. The Q O ) 

 human disease is found both in chil- 

 dren and adults and is regularly fatal. It is characterized by an 

 irregular fever, severe anemia, swelling of the lymph nodes, edema 

 and disturbance of the nervous system. 



LEISHMANIA. This genus was founded by Ross in 1903 for the 

 Leishman-Donovan and Wright bodies found in kala-azar and Delhi 

 boil, to which Nicolle added another in 1909, the parasite of infantile 

 splenomegaly. Leishman, Donovan and Wright, working independ- 

 ently, described the first two parasites in 1903, and, although they have 

 received various names, leishmania is now the accepted term. Rogers, 

 Calkins and others, however, class them as herpetomonads, because of 

 the elongated, flagellated form all take in cultures on the Novy-Mac- 

 Neal-Nicolle blood agar medium. It is, however, best to consider them 

 as a separate genus, because of their natural parasitic habits in 

 human beings. Leveran, Fantham and others have shown that it is 

 possible in the laboratory to induce the herpetomonads parasitic in 

 the intestine of various insects to become parasitic in various ver- 

 tebrates. 



1 Bruce, Bull. Trop. Dis., 1916, vii, 68. 



