A manuscript at the National Anthropological Archives containing words in seven different languages—some of which were misidentified in the past as being "Yukian"—is reevaluated in the light of new information. A number of unattributed Yokuts words are identified, and arguments are presented for attributing these to a little-known Delta Yokuts tribelet dialect, Tamukan. Delta Yokuts was probably spoken by a greater number of tribelets than any other Yokuts language (with the possible exception of Valley Yokuts). It is evident that the known tribelet dialects exhibited a fair amount of lexical variation. Since Delta Yokuts is one of the least attested Yokuts languages, any new information concerning it is welcome.