Travels of an Insect.

New Zealand Mail, Issue 1424, 15 June 1899, Page 14

Travels of an Insect.

TROUBLESOME SOUTH AMERICAN NATIVE’S SLOW, STEADY lOUH ROUND THE WORLD. The jigger, one of the insect pests of the West Indies and South America, has at last crossed the equatorial Africa from the Atlantic to Zanzibar, about 2700 miles, twenty-six years after its introduction into the Continent. This variety of the flea, is very troublesome, and if its attacks upon a few animals, including man, are not prevented, it is sometimes fatal to life. The fact that its gradual advance among the natives of Africa threw them into consternation, often causing the abandonment of villages and districts, has made it easy to trace its progeress step by step, and a linel summary of its journey across Africa will be interesting as a striking Illustration of,insect navigation. A sailing vessel arrived at Ambriz, Angola, in September, 1872, from Brazu with sand ballast, which she dumped on the beach. The jigger had, crossed the ocean in this sand, and its propensity for boring through the skin and lodging between the cuticle and the flesh soon made its presence known. There ore effective means of preventing its Macks, hut before the natives learned how to deal with it the little pest caused great suffering. It was long ago evident that the jigger was not using its own powers of locomotion to any large extent in its journey through Africa, but that it was carried by caravans in the porterage service. In 1885 travellers crossing the Continent from Zanzibar heard nothing of the jigger till they arrived within 309 miles of the Atlantic. It had taken the insect thirteen years to penetrate this distance into Africa, The natives at Stanley Pool had witnessed with sorrow the advent of the unwelcome visitor that abided wick them, but sent on colonies further up the river. Thenceforth the jigger’s progress was more rapid, for steamboats and caravans were multiplying on the upper Congo. Seven years, later, in 1892, Dr Oscar Baumann reported the arrival of the pest at Buliumbi Gulf, midway on the south coast of Victoria Nyanza. It was still unknown on the east shores of the lake. The natives declared that it had been brought to the west coast by Stanley’s expedition for the relief of Emin Pasha. However, that may be, the jigger appeared about the same time throughout most of the cen-

tral lake region, following the caravan route from the upper Congo through Manycina to Lake Tanganyika. _ The natives along the edge of Victoria Nyanza suffered terribly from the infliction and many villages were abandoned. Three years more elapsed before the, missionaries at Mpwapwa reported the arrival of the jigger among the mountains at that point, 200 miles from the Indian ocean. It took the insect two years more to reach the coast towns of East Africa, where it appeared almost simultaneously, late in 1897, at all the towns between Bagamoya and Pangani, along seventy miles of the coast, and another yqor elapsed before, late last fall, it was jumping along the sands of Zanzibar island.

The people of the east coast have suffered comparatively little in comparison with the inland tribes, for hundreds of Zanzibaris who had worked for years on the Congo have returned home and spread the information that rubbing with tobacco leaves and, above all, cleanliness, and the wearing of shoes, are effective protection against the jigger. After its long journey from Brazil the jigger" is now established at the busy mart whence many vessels sail for the East Indies and Oceanica. There seems no good reason why this persevering and successful traveller should not girdle the tropical world.