A study (replicating a similar 1977 study by S. Stotsky), examined whether current basal series teach prefixion clearly. Teacher's guides, student texts, and workbooks of nine popular basal reader series were examined to ascertain whether they offered a clear definition of the term "prefix" and whether that definition was reinforced by the use of correct exemplars. The series examined were published by D.C. Heath; Harcourt-Brace-Jovanovich; Holt Rinehart and Winston; Houghton Mifflin; Macmillan; McGraw-Hill; Open Court; Scott Foresman; and Silver-Burdett and Ginn. Results showed that confusion exists in the definition of "prefix" and that this confusion is frequently compounded by the use of exemplars which mix prefixed words with words with etymological elements which are therefore noncomposite in English. (Five tables of data are included; 24 references and an appendix listing the reading series used in the Stotsky suty are attached.) (SR)