To the Editor.
—As Dr. Benton indicates we did not disprove his work, nor did we propose to do so. If mixed dominance is such an important factor in "the less severe type" of dyslexia, it is hard to understand why Dr. Benton has failed to find an even higher incidence of "dominance abnormalities" in his more severe cases.While there is no general agreement about the criteria for diagnosis of developmental dyslexia, the definition used in our study in the Archives (78:722-729 [Dec] 1967) corresponds to the one most frequently used at present in the English-speaking world. We question the desirability of inclusion of all children who are poor readers under the label of dyslexia. As Shankweiler1 commented, The term "developmental dyslexia" is worth retaining, because it refers to a group of disorders which are profitably to be distinguished from the mass of cases of reading backwardness.