The inhabitants of certain areas of Central Asia suffer severely from a sickness that is caused by a parasitic worm lodged under the skin and known by the natives as “guinea worm.” In April or May there appears under the skin a foreign cylindrical body that lengthens gradually, about 1 inch a week; it lies either stretched out or rolled up in a ball. Often several of them lie together, forming a ball about 1¾ inches in diameter. Subsequently, on the spot of skin underneath which lies the head of the parasite, an abscess appears. In the wound thus formed one can see the head of the worm. Depending upon the area of the body in which the parasite develops, the pain of the attack differs. Since most often the parasite appears in the lower extremities, the diseased person usually lies on his back while the abscess is acute, trying to avoid pain by not moving his legs.