FEB., 1912. MAMMALS oF ILLINOIS AND WISCONSIN — Cory. 203 
Measurements — (Average of 8 specimens from various localities.) 
Total length, 8.88 in. (225 mm.); tail vertebra, 4.38 in. (111 mm.); 
hind foot, 1.15 in. (29.6 mm.). 
The Rice Field Mouse occurs within our limits in southern Illinois, 
where Mr. Howell secured four specimens taken at Olive Branch, Alex- 
ander Co. In Louisiana and northwestern Florida, where I have taken 
it, it inhabits swampy places, hummocks, and old fields, but apparently 
never far from water, in which it is quite at home, being an expert 
swimmer. In such localities the nest is in a burrow in the ground, 
but Audubon and Bachman state that in extensive salt marshes they 
ONTARIO 
bad 
V4aG 
WMA, 
he Oryzomys palustris 
—_, O. p. coloratus 
aan PAIS 
AN ‘Area of intergradation 
OF mexte? 
Map illustrating the approximate distribution of Rice Field Mice or Rice Rats of the genus 
Oryzomys which occur in eastern United States. 
Oryzomys palustris (HARLAN). Type locality — Fast Land, near Salem, Salem Co., 
New Jersey. Description as previously given. 
Oryzomys p. natator CHAPMAN. (Bull. Amer. Mus. Nat. Hist., V, 1893, p. 44.) Type 
locality — Gainesville, Alachua County, Florida. Larger than palustris and 
tail longer; color more fulyous brown. 
Oryzomys p. coloratus BANGS. (Proc. Bost. Soc. Nat. Hist., XXVIII, 1898, p. 189.) 
Type locality — Cape Sable, Monroe Co., Florida. Larger than matator; 
color more reddish brown. 
