we epitomized the principal data which document the existence of parasite carriers in ankylostomiasis, the rôle of nutrion in this disease and in anaemia in general, and also the various ideas concerning the pathogenesis of this verminosis. We presented five cases of ankylostomiasis associated by severe anaemia (Hb. from 13 to 30%), cured and so preserved by means of daily iron administration for a long time (3 to 10 months), despite the persistence of very intense infestations (25 to 40 thousand eggs of ankylostoma per gr. of faeces). During the period of maintenance, different examinations were made which always presented normal readings or approaching normal. The only exception was the verification of intense eosinophilia in peripheral blood. Thus then are determined which disturbances may be corrected by iron and which derive from a direct action of the parasite worm. Finally, the secondary action of the helminth is discussed with regard to the preponderant influence of food, laying stress on the essential importance of the richness of diet in iron.