Considerable information has been recorded concerning the food of _Mustela frenata_ and a little information is on record as to kinds of foods not taken that could have been taken. For example, Ingles (1939:253, 254) on May 14, 1938, near Shasta City, California, noted that nestlings of russet-backed thrushes were ignored by an adult weasel and four young weasels which were feeding instead on meadow mice and a mole. Howard (1935:322, 323) records that a weasel in Michigan which carried bits of meat from beef bones on a porch ignored a red squirrel which drew on the same food supply but which retreated to the end of the porch when the weasel appeared. Quick (1944) records that in the winter of 1940 on a 640 acre area in Washtenaw County, Michigan, four resident weasels did not kill any of the 10 rabbits or several pheasants but subsisted on smaller animals. Glover (1943A) thought that _M. frenata_ kills only a few adult cottontails in the wild. To judge from these observations, _M. frenata_ chooses small mammals as prey in greater measure than it does birds or larger mammals. Records of prey taken, attacked or pursued by _Mustela frenata_ include the following: Broad-footed mole (_Scapanus latimanus_).--One was fed on by an adult _M. frenata_ and four young, on May 14, 1939, "near Shasta City," California (Ingles, 1939:253, 254). Dusky shrew (_Sorex cinereus_).--A female weasel, at Majestic, Long Island, N. Y., was shot when carrying a _Sorex cinereus_ that had a small hole in the top of its head (Nichols and Nichols, 1935:297-299). Big short-tailed shrew (_Blarina brevicauda_).--One was taken from the stomach of a weasel (Hamilton, 1928:249). Townsend ground squirrel (_Citellus townsendii_).--Alcorn saw a weasel five miles west of Fallon, Nevada, carrying a squirrel (Hall, 1946:192). Richardson ground squirrel (_Citellus richardsonii_).--The attempted capture of one of these squirrels in Saskatchewan is recorded by Seton (1929 (2):625). Belding ground squirrel (_Citellus beldingi_).--Grinnell, Dixon and Linsdale (1937:233) recount that at Tuolumne Meadows, California, a weasel killed a ground squirrel of this species. Thirteen-lined ground squirrel (_Citellus tridecemlineatus_).--Errington (1936:406, 407) found a den in Palo Alto County, Iowa, on June 22, 1934, where he collected 32 fecal pellets. Sixteen samples contained thirteen-lined ground squirrels, 9 contained rabbits, 9 contained mice (7 _Microtus_, 1 _Peromyscus_ and 1 unidentified); red-winged blackbirds and unidentified fringillids were represented as also were ground beetles, grasshoppers and other insects. One red-winged blackbird lay near the entrance of the den.