concentrated where food was abundant but no such concentration was noted in the following winter. Big short-tailed shrew (_Blarina brevicauda_).--In New York State, the ermine preys on _Blarina_ as shown by Hamilton's (1933:330) seeing one being carried by a male ermine on May 6, 1931, and another being carried by a female on May 13, 1932. The same author (1928:249) found the remains of a _Blarina_ in a small female from Malone, New York. Kirk (1921) observed, however, that the ermine (_M. e. cicognanii_) avoided the shrew, _Blarina_, caught in a trap and that _Blarina_ avoided the weasel caught in a trap. Chipmunk (genus _Tamias_).--Remains were found in a male ermine in New York on May 14, 1932 (Hamilton, 1933:330), and Seton (1929 (2):602) records a chipmunk at Lake Couchiching, Ontario, that was pursued into the water by an ermine. Deer mice (genus _Peromyscus_).--As shown by Hamilton (1933:33) and Aldous and Manweiler (1942), _Peromyscus_ was second only to microtines in numerical abundance among the food items of ermines in New York and Minnesota. _Peromyscus_ and microtine rodents were brought to a den of the diminutive _M. e. muricus_ in early August, in Fresno County, California, according to Ingles (1942). He observed that an Alpine chipmunk was active under and around the tree and that juncos reared young 40 feet from the den but that the chipmunk and juncos were unmolested by the ermines. Lemming (genus _Lemmus_).--One was recovered from a female ermine (with milk in her glands) at Laurier Pass, British Columbia (Sheldon, 1932:201). Red-backed mouse (genus _Clethrionomys_).--Criddle and Criddle (1925:146) record that on "May 31, 1921.--Saw a Bonaparte's weasel capture a Red-backed Vole after a long hunt during which the pursuer never once lost track of its victim." Meadow mice (genus _Microtus_).--As shown by the data of Hamilton (1933:333) and Aldous and Manweiler (1942) recorded above, _Microtus_ is the item of first importance in the diet of the ermine in New York and Minnesota. Criddle and Criddle (1925:146) write concerning the vicinity of Treesbank, Manitoba, that "October, 1918.--Following a severe outbreak of mice in 1916-17, Bonaparte's weasel increased enormously and very soon reduced the rodents to comparative rarity. This resulted in a scarcity of food for the weasels, which in their turn became greatly reduced in numbers." Old World rat (_Rattus_).--Bishop (1923) found two headless rats near a nest of this species in Albany, New York. Pika (_Ochotona_).--Dixon (1931:72) at Milner Pass, Colorado, on July 20, 1931, saw an ermine, of the subspecies _muricus_, following a three-fourths grown pika by scent and outrunning the pika. The pikas worked a relay system and the weasel abandoned the trail when the fourth pika became the object of the chase.