National Geographic : 1942 Dec
The National Geographic Magazine To Tsetse Flies This Trap Looks Like a Cow Lured by the light-colored burlap, flies crawl underneath. Finding no blood, they fly up to the light only to be trapped in the cage. Thousands of traps placed in infected areas, especially in Natal, have greatly reduced the tsetse-fly disease (nagana) among livestock. Wild game in the bush are also victims (page 766). Say Ah, Little Sheep, and Take Your Medicine Nearly 22 million doses of worm compound are prepared yearly at this veterinary center at Onderstepoort.