208 ENTOMOLOGY FOR MEDICAL OFFICERS 



Conorhinus infestans is a well-known blood-sucker in 

 South America ; it is spoken of by Darwin as " the great 

 black bug of the pampas." Conorhinus sanguisuga is another 

 nocturnal blood-sucker in America: it is coloured dark 

 brown with reddish markings. 



Conorhinus megisius, Burm., is a large black species, with 

 numerous regularly arranged red markings, and is common 

 in huts in certain parts of Brazil, where it is known as 

 " Barbeiro." It is not merely a voracious nocturnal blood- 

 sucker, but has also also been found by Chagas to interpose 

 in the developmental cycle of a trypanosome {T. cruzii) 

 which is parasitic in the blood of human beings and produces 

 symptoms which somewhat resemble those of kdla-azdr and 



Pig. 92.— CoTOOrAwiiS. 



pellagra combined. The trypanosomes are said to be 

 injected into man with the saliva of the bug when the insect 

 bites. Reaching the capillaries of the lungs they are said 

 there to become quiescent and to multiply by schizogony. 

 The resulting merozoites pass from the lungs into the general 

 circulation, where they are said to lodge and grow in the red 

 blood cells, destroying these, and at last becoming free 

 trypanosomes in the blood-plasma. In the bug it is said 

 that the imbibed trypanosomes, after becoming pear-shaped, 

 multiply by fission in the stomach; that the pear-shaped 

 products of fission become Crithidiform, and then again 

 multiply by fission in the intestine ; and that the Crithidia 

 forms, having acquired the undulating membrane, are ulti- 

 mately found as trypanosomes in the body-cavity and salivary 

 glands. 



A nocturnal species that is sometimes found in houses in 



