A Wherry and Wherry (1969) hierarchical factor solution was obtained on WISC-R subtest intercorreations for a sample comprised of 112 reading disabled children. A hierarchical ability arrangement congrument with Vernon's (1950) structural paradigm was obtained. The hierarchy included a general (g) factor, two subgeneral factors corresponding to the verbal-educational (v:ed) and spatial-perceptual-mechanical (k:m) dimensions from Vernon's paradigm, and four primary factors corresponding to those obtained by Cohen (1959) in his classical analysis of WISC.