A total of 76 stcol specimens were examined by the Kato method (as modified by Martins and Beaver), and a comparison made with Hoffman's sedimentation method. With the sole exception of infections by T. trichiurus, in which Kato's method was clearly superior, the author was unable to confirm the alleged virtues of this procedure, at least under the conditions of the clinical laboratory . The author wishes to stress, however, that it has not been possible to test the method in S. mansoni infections, due to lack of positive specimens. In this field the absence of a technique adequate for the diagnosis of light infections is accutely felt, and it would be possible to antecipate more hopeful results by the use of the Kato procedure.