282 Trypanosomiasis 
the flies become infective and remain infective indefinitely. There is 
evidence that certain of these trypanosoines favour definite species of 
Glossina as hosts ; if it were not so the flagellates would be even more 
widely distributed geographically than they are at present. 
Chagas' Disease. 
Schizotrypanum erxizi Chagas, 1909, the cause of trypanosomiasis in 
Brazil, is transmitted by a reduviid bug, Conorhinus megisfus. This vector 
occurs all over Brazil in badly kept clay and wooden houses and is a 
night feeder, the adult insect being able to fly. The bug moults five 
times before attaining sexual maturity in about 324 days. The bug 
becomes infective eight daysafter feeding upon infected blood and remains 
infective over a year. A female may live over 57 days without food. 
The parasites, which are numerous in the blood in acute cases, 
multiply in the midgut of the bug. They are at first rounded, then 
crithidia-like, they then assume the trypanosome form in which they 
occur in the gut and salivary glands of the bug. Infection occurs 
through the infected saliva of the bug introduced in the act of biting, 
but the bug’s excreta are also infective when fresh. I may add that 
Brumpt has recently observed the development of T. cruzi in Oimex 
lectularius and G. boueti. 
The disease is communicable to dogs, cats, rabbits, guinea-pigs, rats, 
mice, and monkeys {Cercopithecus ruber, Hapale and the Sajou). It is 
peculiar compared to other forms of trypanosomiasis, the thyroid gland 
being at times much enlarged (goitre-like). In some chronic cases there 
occur motor and cardiac disturbances, convulsions, infantilism and idiocy, 
etc. 
Trypanosoma boylei Lafont, 1912. 
Another interesting parasite of a reduviid bug, Conorhinus 
rubrofasciatus, has been reported upon this year by Lafont. The 
insect, which attacks man in Mauritius and Reunion, has been found to 
harbour flagellates, the intestinal tract of 50 to 80 "/o of the bugs 
containing the parasites. Lafont infected rats and mice by intra- 
peritoneal injection with the gut contents of the bugs. In rats the 
parasites remain confined to the peritoneal cavity whence they 
disappear in. about 30 hours. In mice, on the other hand, the 
flagellates appear in the blood stream in from five to seven hours after 
inoculation and persist there for one to five days, after which they 
