The male fern is a very ancient remedy for tape-worm, and to the present day physicians have found nothing so successful for removing this parasite. The plant is indigenous to Canada, Mexico, South America, India, Africa, and Europe. The negroes of South America have long used worm-seed (_Chenopodium anthelminticum_) as a vermifuge for lumbricoid worms. The plant grows wild in the United States, and has been introduced into the Pharmacopœia as a remedy especially adapted for the expulsion of the round-worms of children. Kousso (_Brayera anthelmintica_) has been employed from time immemorial in Abyssinia for the expulsion of tape-worm. It has been introduced into the British Pharmacopœia. Some tribes of the Upper Orinoco, Rio Negro, etc., have been known to subsist for months on no other food than an edible earth, a kind of clay containing oxide of iron, and which is of a reddish-brown colour. M. Cortambert, at a meeting of the Geographical Society in 1862, described this singular food, and said it seemed to be rather a stay for the stomach than a nourishment. Some white people in Venezuela have imitated the earth-eaters, and do not despise balls of fat earth.[84] Savages require much larger doses of drugs than civilized people. Mr. Bonney relates[85] that he usually gave the aborigines of New South Wales half a pint or more of castor oil for a dose. Another man took three drops of croton oil as an ordinary dose. Professor Bentley in 1862-63 contributed to the _Pharmaceutical Journal_ a series of articles on New American Remedies which have been introduced into medical practice in consequence of their reputation amongst the Indians. Yellow-root (_Xanthorrhiza apiifolia_) has long been employed by the various tribes of North American Indians as a tonic, and may be compared to quassia or calumba root. It is included in the United States Pharmacopœia. Its active principle seems to be _berberine_. The blue Cohosh plant (_Caulophyllum thalictroides_) has for ages been used by the aborigines of North America as a valuable remedy for female complaints. A tea of the root is employed amongst the Chippeway Indians on Lake Superior as an aid to parturition. The earliest colonists obtained their knowledge of the virtues of the blue cohosh from the natives, and it has for many years been a favourite diuretic remedy in the States. Its common names are pappoose-root, squaw-root, and blueberry-root. Its active principle is called _caulophyllin_. Twin-leaf (_Jeffersonia diphylla_) is a popular remedy in Ohio and other North American States in rheumatism. It is called _rheumatism-root_. In chemical composition it is similar to senega.