TRIATOMA 381 



known to infect these animals in nature, and the armadillo is 

 possibly an important reservoir of the disease. Triatoma chagasi 

 which had fed on a rodent known as the " moco," Cerodon 

 rupestris, in an uninhabited desert region was found to be infected. 

 T. vitticeps, occurring near Rio de Janeiro, T. sordida of Sao 

 Paulo and T. dimidiata of San Salvador in Central America 

 have been found infected with trypanosomes thought to be iden- 

 tical with the species causing Chagas' disease, and these species 

 have been shown to be capable of transmitting the infection to 

 guinea-pigs. In Argentina, as well as throughout most of 

 Brazil, T. infestans, the vinchuca or " great black bug of the 

 Pampas," described by Darwin in his " Voyage of a Naturalist " 

 as a vicious human pest, has been found to harbor a similar 

 trypanosome, but whether or not Chagas' disease exists in 

 Argentina is still in doubt. T. protrada of southwestern United 

 States has been shown recently by Kofoid and McCulloch to 

 harbor a trypanosome which exhibits only slight differences from 

 Trypanosoma cruzi, and, as intimated by the discoverers, may 

 possibly be merely a variety of the same species though named 

 by them T. triatomce. The widely distributed T. rubrofasciata 

 was shown by Neiva to become infected with trypanosomes after 

 feeding on an infected guinea pig. From all this evidence, and 

 from the fact that other species of bugs of different genera and 

 families, including the bedbugs, are experimentally susceptible 

 to the infection and capable of transmitting it to rodents, it is 

 possible that all the species of Triatoma and allied genera in South 

 and Central America may be potential transmitters of the in- 

 fection. Cannibalism is common among many of these bugs, 

 and may make possible a direct spreading of trypanosome in- 

 fection from bug to bug. 



The " Malay bug," T. rubrofasciata, of tropical Asia and some 

 parts of Africa and Madagascar is a closely allied species. With 

 its huge proboscis it produces a nasty sting which is followed in 

 a few minutes by acute pain and swelling. Although it feeds on 

 man by preference, it attacks a number of other mammals and 

 even insects. Large nymphs or adults, which are an inch or 

 more in length, are said to consume about one cc. of blood at 

 a meal, and they feed at intervals of from three to six days. The 

 breeding habits are similar to those of other cone-noses. In 

 the islands of Mauritius and Reunion the stomach and intestines 



