Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
vŏlūtātus, ūs, m. [voluto], a rolling about, wallowing (post-Aug.): pulvis volutatu collectus, Phn. 10, 4, 5, § 17.
Plur.: volutatibus pulvereis, App. M. 4, p. 144, 39.