There have been several recent works dealing with the Russian "root system." Most of these works operate on the claim that vocabulary-building in advanced Russian classes may be accelerated by a mastery of the systems of derivational morphology. Townsend's "Russian Word Formation," Gribble's "Russian Root List," and Beard's "Dynamic Glossing" (SEEJ 19,49-57) are all predicated on the assumption that knowing the roots, affixes, and rules of combination of Russian derived words will facilitate vocabulary-building. This paper reports on two experiments designed to test the validity of "root theory." In the first test, experimental subjects were given a list of Russian words sectioned into individual morphemes, while the control subjects received a list of the same words unsectioned in lower case type. It was found that the experimental subjects remembered more words on the recall tests. In the second experiment, all subjects were given the same list of new, unfamiliar words but which comprised morphemes occurring in the previous recall experiment. It was found that although the difference was not of statistical significance, the experimental group outperformed the control group in identifying the correct meaning of the new words in a fashion paralleling its performance on the recall test. (Author)