Identical rhymes (right/write, attire/retire) are considered satisfactory and even artistic in French poetry but are considered unsatisfactory in English. This has been a consistent generalization over the course of centuries, a surprising fact given that other aspects of poetic form in French were happily applied in English. This paper puts forward the hypothesis that this difference is not merely one of poetic tradition, but is grounded in the distinct ways in which information-structure affects prosody in the two languages. A study of rhyme usage in poetry and a perception experiment confirm that native speakers' intuitions about rhyming in the two languages indeed differ, and a further perception experiment supports the hypothesis that this fact is due to a constraint on prosody that is active in English but not in French. The findings suggest that certain forms of artistic expression in poetry are influenced, and even constrained, by more general properties of a language. (Contains 1 table and 2 figures.)