The Reading Comprehension and Spelling subtests of the Stanford Achievement Test were administered to 170 eighth grade students to test four null hypotheses about the differences between reading ability, spelling ability, and phonic generalization spelling errors. In addition, a specially constructed Phonics Generalization Spelling Test was administered. The results indicate significant differences in the reading achievement of good and poor spellers, and in the spelling achievement of good and poor readers. A qualitative analysis of phonic generalization spelling errors also finds that qualitative differences occur in the errors made by good and poor readers and by good and poor spellers. (RL)