In the "Sound Pattern of English," Chomsky and Halle (1968) posited that English orthography, despite the complexity in how it relates to phonology, is in fact more "optimal" in at least one aspect: how it relates to morphology. A root or stem tends to maintain a constant visual form across words built upon it even as its pronunciation alternates considerably across derivatives. The suggestion is that a spelling system which makes strategic concessions to the regularity of its grapheme-phoneme correspondences in order to render morphological links between words more visually obvious, such as English, may better facilitate comprehension than a system which prioritizes consistency of symbol-to-sound mapping above all else, such as Spanish. In order to test this hypothesis, groups of native Anglophones and native Hispanophones were given a lexical decision task in their respective mother tongues. Stimuli included morphologically related prime/target pairs that instantiate common patterns of phonological stem allomorphy. In Spanish, the written form of each shared stem differed between prime and target whenever its pronunciation alternated, while in English, the shared stem was spelled identically regardless of alternation. The degree of facilitation seen between primes and targets in English was compared to that observed in Spanish. In a second experiment, cloze tests of reading comprehension were administered in both tongues. Within each language, scores were tested for any correlation with morphological priming, and across both languages, average scores were compared. The results reveal no evidence for such a benefit of morphological transparency, as no significant difference between facilitation effects was found between the two languages, nor were the cloze test scores significantly different. What the results did show is evidence of an inhibitory effect of orthographic overlap on reaction times in both languages as well as hints at interaction(s) between priming direction, lexical ambiguity, and language. The absence of any significant difference in morphological priming between alternating and non-alternating pairs as well as between languages has implications for the debate between full-listing and full-decomposition models of lexical access as well as the relative merits of deep versus shallow orthographies. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]