430 



TR YPA NO SO MI DM 



Brumpt finds that the parasite lives well in Clinocoris ledularius, 

 C. rotundatus, CUnocoris boueti, and Ornithodorus mouhata. His 

 account of the cycle of development is as follows : — Starting with the 

 trypanosome in the posterior part of the intestine, when this is 

 inoculated into the vertebrate, it enters the cells of the body, and 

 becomes Leishmania-like bodies, which eventually develop into 

 free-swimming trypanosomes, from which the form capable of 

 continuing the infection in the vertebrate or invertebrate is pro- 

 duced. In the invertebrate these become crithidia-like forms, and 

 eventually trypanosomes capable of infecting vertebrates, and thus 

 completing the cycle of life-history. 



Brumpt and Gonzalez-Lugo have found the parasite in the faeces 

 of Rhodnius prolixus two months after infection. Triatoma vitticeps 

 and T. diminuata are also carriers, as is T. sordida Stal and Rhipi- 

 cephalus sanguineus. 



Culture. — 5. cruzi is easily cultivated upon the Novy-McNeal 

 medium, when the first changes begin in about six hours, and closely 

 resemble those already described in the bug. 



Pathogenicity. — Two to three days after an infective feed the 

 larvae of Lamus cease to be infective to vertebrates, and first 

 become so on the eighth to the tenth day, after which they remain 

 infective for a long period. The parasites so introduced into man 

 give rise to American trypanosomiasis. 



Reduction in Virulence. — 5. cruzi, when repeatedly passed through 

 animals of the same species, become Weakened in virulence, but 

 regain this when transmitted to a fresh species. 



Infeetivity. — -The infected monkey is infective for the bug, while 

 the infected guinea-pig is not. 



Duttonella vivax Ziemann, 1905, var. macfiensis. 



Synonym.' — Trypanosoma vivax (Ziemann, 1905) pro parte. 



In 1917 Macfie described a monomorphic trypanosome very 

 closely resembling T. vivax, but slightly smaller, with the crest in 

 curves of measurements at 21 instead of at 23 microns. It is said 

 to be intermediate between T. uniforme and T. vivax. 



It was found in the blood of a man suffering from trypanosomiasis 

 on the Gold Coast, where T. vivax is common in the humpbacked 

 cattle at Accra. The maximum length Was 24 microns, the minimum 

 18 microns, and the average 207 microns. 



It is monomorphic, with abrupt narrowing of the body immediately 

 anterior to the trophonucleus. The posterior (aflagellar) end is blunt, 

 and the large rounded kinetonucleus is terminal or nearly so. The 

 undulating membrane is narrow, and there is always a long free 

 flagellum. 



Castellanella nigeriensis Macfie, 1913. 



This trypanosome M^as found in cases of human trypanosomiasis from the 

 Eket district of Southern Nigeria, by Macfie, where it was common in young 

 people. It appears to give rise to a not very virulent, non-epidemic form of 

 trypanosomiasis. It is polymorphic, and in our opinion is the same parasite 



