THE TSETSE POISON. ?r 



an oily consistence. All the muscles are flabby, and the 

 heart often so soft that the fingers may be made to meet 

 through it. The lungs and liver partake of the disease. 

 The stomach and bowels are pale and empty, and the gall- 

 bladder is distended with bile. 



These symptoms seem to indicate what is probably the 

 case, a poison in the blood ; the germ of which enters 

 when the proboscis is inserted to draw blood. The poison- 

 germ, contained in a bulb at the root of the proboscis, 

 seems capable, although very minute in quantity, of 

 reproducing itself, for the blood after death by tsetse is 

 very small in quantity, and scarcely stains the hands in 

 dissection. I shall have by- and- by to mention another 

 insect, which by the same operation produces in the human 

 subject both vomiting and purging. 



The mule, ass, and goat enjoy the same immunity from 

 the tsetse as man and the game. Many large tribes on 

 the Zambesi can keep no domestic animals except the 

 goat, in consequence of the scourge existing in their 

 country. Our children were frequently bitten, yet 

 suffered no harm ; and we saw around us numbers of 

 zebras, buffaloes, pigs, pallahs and other antelopes, feeding 

 quietly in the very habitat of the tsetse, yet as undis- 

 turbed by its bite as oxen are when they first receive the 

 fatal poison. There is not so much difference in the 

 natures of the horse and zebra, the buffalo and ox, the 

 sheep and antelope, as to afford any satisfactory explana- 

 tion of the phenomenon. Is a man not as much a domestic 

 animal as a dog ? The curious feature in the case, that 

 dogs perish though fed on milk, whereas the calves escape 

 so long as they continue sucking, made us imagine that 

 the mischief might be produced by some plant in the 

 locality, and not by tsetse ; but Major Vardon, of the 

 Madras Army, settled that point by riding a horse up to 

 a small hill infested by the insect without allowing him 

 time to graze, and, though he only remained long enough 

 to take a view of the country and catch some specimens 

 of tsetse on the animal, in ten days afterwards the horse 

 was dead. 



The well-known disgust which the tsetse shows to 

 animal excreta, as exhibited when a village is placed in 

 its habitat, has been observed and turned to account by 

 some of the doctors. They mix droppings of animals, 

 human milk, and some medicines together, and smear 



