492 MEDICAL ENTOMOLOGY 



Conorhinus rubrofasciatus, variety mexicana, Neiva. Proboscis, head 

 and pronotum chestnut brown ; scutellum, which ends in a slender 

 point, of the same colour. Corium and membrane dark brown; in two 

 specimens examined by Neiva there were clear areas at the base and 

 apex of the corium. Connexivum with dark dots separated by ochra- 

 ceous lines. Ventral surface of body and legs dark brown. 



This variety the type of which is in the British Museum, is found in 

 Mexico ; its habits and early stages are unknown. 



Conorhinus megistus, Burm. (Plate LIX, fig. 2). Dark brown to 

 black. Pronotum broadly expanded, with two broad raised red lines ex- 

 tending from the middle to the posterior border, and a red spot on the 

 postero-lateral angles of pronotum. At the anterior border of the prono- 

 tum there are six short spines, three on each side ; the most anterior are 

 the longest and project on each side of the eyes ; two are situated further 

 back, one on each side of the middle line at the origin of the two 

 admedian ridges ; the third spine is situated on a ridge at the junction of 

 the middle and anterior third of the pronotum just above the first pair 

 of legs. Scutellum dark brown with two short red lines converging 

 towards the apex, where they meet; apex red, turned upwards and 

 bluntly rounded off. Corium and membrane fuscous, the former with 

 one or more red streaks. Connexivum with six well marked bright 

 red lines, broader in the male ; in both sexes the lines extend round to the 

 ventral border. In the male the last segment, except for a central 

 black mark, is entirely red. Length 30 to 32 mm. 



This large dark species is widely distributed in Brazil. In the States 

 of Minas Gaeras, Sao Paulo and Motto Grosso it is popularly known as 

 the ' Barbeiro' (barber), and in the southern parts of the latter state as 

 ' Chupanca ' or 'Chupao'; in Rio Grande de Sul it is spoken f as ' fincao ' 

 and in some of the northern states of Brazil as ' bicho de parede ' (wall 

 insect). Neiva states that megistus also occurs in British Guiana. 



As has already been noted Conorhinus megistus is the invertebrate 

 host of Trypanosoma cruzi, Chagas. In certain localities in the State of 



Minas Gaeras the disease caused by this parasite often 

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disease attacks the entire population ; children develop it dur- 



ing the first years of their lives and then either die 

 or pass into the chronic form, which may last a long time. The parasite 

 has been successfully transmitted by the bite of Conorhinus megistus to 

 monkeys, guinea pigs, rabbits and dogs, to all of which it is pathogenic. 

 Chagas believes the parasite has two forms of development in its 

 invertebrate host. In one there is a simple culture of the parasite in the 



