Guineaworm

Guinea-worm (Filaria medinensis), belongs to the order Nematoda or Threadworms. The adult form lives beneath the skin of man and, more rarely, of the horse; it occurs in the tropical parts of Africa and Asia, occasionally also in the West Indies. A length of six feet is sometimes reached. Very numerous living young are produced, escape from their host and, for a time, swim freely in fresh water; they then bore their way into the body of a small crustacean, Cyclops, where they undergo further development, but the sexually mature condition is only attained when the Cyclops is sw-allowed by a man or a horse, through whose tissues the young worms make their way to a position beneath the skin, usually of the feet or legs