Abstract
Langacker's usage-based model provides cognitive linguists with a useful tool for the study of allomorphy. In the present article the model is applied to a central problem in Russian conjugation, viz., the formation of the past passive participle. The analysis demonstrates the restrictiveness of the model, which precludes reference to arbitrary indices and underlying representations. Thus, the analyst is forced to look for surface-true generalizations including phonological, semantic, and symbolic structures and relationships holding between them. This reseach strategy proves fruitful for the Russian past passive participle. The choice of suffixes is shown to be predictable from the shape of the past-tense stem, facilitating the formation of simple generalizations about the distribution of the relevant suffixes.