230 THE TROPICAL WORLD. 



A most remarkable feature in the bite of the tsetse is its 

 perfect harmlessness in man and wild animals, and even calves, 

 so long as they continue to suck the cow. The mule, ass, and 

 goat enjoy likewise the same immunity, and many large tribes 

 on the Zambesi can keep no domestic animals except the 

 latter, in consequence of the scourge existing in their country. 

 Dr. Livingstone's children were frequently bitten, yet suffered 

 no harm, and he saw around him numbers of zebras, buffaloes, 

 pigs, pallahs and other antelopes, feeding quietly in the 

 very habitat of the tsetse, yet as undisturbed by its bite as oxen 

 are when they first receive the fatal poison, which acts in the 

 following manner. After a few days the eyes and nose begin 

 to run, the coat stares as if the animal were cold, a swelling 

 appears under the jaw, and, though the animal continues to 

 graze, emaciation commences, accompanied with a peculiar 

 flaccidity of the muscles ; and this proceeds unchecked until, 

 perhaps months afterwards, purging comes on, and the animal, 

 no longer able to graze, perishes in a state of extreme ex- 

 haustion. Those which are in good condition often perish, 

 soon after the wound is inflicted, with staggering and blindness, 

 as if the brain were affected by it. Sudden changes of tempera- 

 ture, produced by falls of rain, seem to hasten the progress of 

 the complaint, but in general the emaciation goes on unin- 

 terruptedly for months ; and do what one may, the poor 

 animals perish miserably, as there is no cure yet known for the 

 disease. 



Had any one of our indigenous flies similar poisonous 

 qualities we should never have been able to escape from bar- 

 barism ; if, by any fatal chance, the tsetse were to settle among 

 us, our prosperity would soon be at an end, and our civili- 

 sation imperilled ! Eeflections such as these are well calcu- 

 lated to humble our pride and check our presumption I 



The Abyssinian Tsalt-salya or Zimb, described by Bruce, 

 seems identical with the tsets^, or produces at least similar 

 symptoms. At the season when this plague makes its appear- 

 ance, all the inhabitants along the sea-coast, from Melinde to 

 Cape Grardafui, and to the south of the Red Sea, are obliged to 

 retire with their cattle to the sandy plains to preserve them 

 from destruction. 



The French traveller, D'Escayrac, tells us of a fly in Soudan 



