_=Eutamias umbrinus umbrinus=_ (J. A. Allen). Uinta Chipmunk.--Two specimens, numbers 10,236 and 10,237, from the junction of Argyle and Minnie Maud creeks, Carbon County, prove that members of this subspecies occur on the West Tavaputs Plateau, which is outside the range ascribed to this subspecies by White (1953:572) and by Durrant (1952:142). The grayish color of these specimens and the reduction of ochraceous pigments constitute basis for referring the specimens to _E. u. umbrinus_, and not to _E. u. adsitus_ or _E. u. montanus_. _E. u. umbrinus_ on the West Tavaputs Plateau is separated from _E. u. montanus_ on the East Tavaputs Plateau by the Green River and its deep chasm. _=Perognathus formosus incolatus=_ Hall. Long-tailed Pocket Mouse.--Prior to the description of this subspecies by Hall (1941:56), animals of this species had not been reported from within the basin of the Pleistocene Lake Bonneville. When Durrant (1952) prepared his manuscript he had but a single specimen from western Millard County and one nearby record (Fautin, 1946:280). Additional specimens are known from the following localities: junction of Trout Creek and Birch Creek, Deep Creek Mountains, Tooele County; six miles north of Ibapah, Tooele County; five miles south of Timpie, Tooele County; north end of Newfoundland Mountains, Boxelder County; and Groome, Boxelder County. These occurrences show that the species is not restricted to the extreme western part of the state, but occurs in suitable habitats throughout the basin of Pleistocene Lake Bonneville. The known range is extended approximately 150 miles north and 40 miles east. _=Perognathus parvus trumbullensis=_ Benson. Great Basin Pocket Mouse.--Durrant (1952:477), suspecting that this mouse occurred in Utah, included the subspecies _P. p. trumbullensis_ in his hypothetical list. Numerous specimens are now available from the following localities: Pine Valley Mountains, Enterprise Reservoir, and 19 miles west of Enterprise, Washington County; Bown's Reservoir, Snow Ranch, Hall Ranch, Steep Creek, Garfield County; Aquarius Guard Station, Aquarius Plateau, Wayne County. Insofar as we are aware, these occurrences are the first to be recorded from Utah, and extend the known range of this subspecies 150 miles northward.