FEs., 1912. MamMats oF ILLINoIs AND WIsconsIN— Cory. 235 
Goss'’s Lemming Mouse (Synapiomys cooperi gossii) . 
“This mouse is found on hillsides in high, dry, blue grass pastures, 
where flat stones are irregularly scattered over the surface; it especial- 
ly prefers what are known as ‘wood pastures’ containing little or no 
undergrowth. . . . Cooper’s field mouse has been found breed- 
ing from February to December. It has never been known by the 
authors to bring forth more than four young at a time. . . . The 
nest of this species is always under cover, generally in a hollow log or 
stump, and is composed of fine grass. It is not so securely built as the 
nests of some of the other species of this family. 
“‘Cooper’s mice live in winter chiefly upon the stems of blue grass 
and the more tender portions of the white clover. Stores of these foods 
may be found near their winter quarters. In November, 1883, a large 
quantity of the tuberous roots of the plant commonly called ‘wild 
artichoke’ (Helianthus doronicoides Lam.) were found in one of the 
store-houses of a colony of these mice. . . . Cooper’s mouse is 
the most active representative of its family in this locality. It is most 
frequently found by turning over stones and logs, beneath which it 
remains concealed, especially in winter. Upon removing their cover- 
ing, as the light reaches them, they are off like a flash for their sub- 
terranean paths, leaving the collector to mourn for a valuable speci- 
men, a glimpse of which he caught as it fled before his hand could 
grasp the prize.” (Amer. Nat., XIX, 1885, pp. 114, 115.) 
