202 Fretp Museum or Naturat History — Zoérocy, Vou. XI. 
of molars tuberculate; front of incisors with distinct longitudinal groove. 
Total length, about 5 in. (120 to 130 mm.); tail vertebre, 2 to 2.50 in. 
(50 to 65 mm.). 
Genus ORYZOMYS Baird. 
Oryzomys Baird, Mammals N. Amer., 1857, p. 458. Type Mus palus- 
tris Harlan. 
Molars or grinding teeth with tubercles on crowns arranged in two 
rows; hair on tail scanty; skull showing a distinct ridge over eye socket; 
belly not white; hind feet large. 
rC. 
r= O= ° 
° oO 
>» Pm. 
o-O0 
oy M. ae 16. 
o-oo 373 
Dental formula: I. or 
Oryzomys palustris (HARLAN). 
Rice Frerp Mouse. Rick Rar. 
Mus palustris HARLAN, Silliman’s Amer. Jour. Sci. & Arts, XXXI, No. 2, 1837, p. 386. 
Arvicola oryzivora AUDUBON & BACHMAN, Quadrupeds of N. Amer., ITI, 1854, p. 214. 
Hesperomys (Oryzomys) palustris BAIRD, Mammals N. Amer., 1857, p. 459. 
Oryzomys palustris MERRIAM, Proc. Wash. Acad. Sci., III, 1901, p. 276. Haun, 
Ann. Rept. Dept. Geol. & Nat. Resources Ind., 1908 (1909), p. 640 (Indiana). 
How8ELt, Proc. Biol. Soc. Wash., XXIII, 1910, p. 26 (Illinois and Missouri). 
Ib., p. 61 (Kentucky, Tennessee, etc.). VAN Hyninc & PELLETT, Proc. Iowa 
Acad. Sci., XVII, 1910, p. 213 (Iowa). 
Calomys palustris EVERMANN & BUTLER, Proc. Ind. Acad. Sci., 1893 (1894), p. 139, 
Type locality — Fast Land, near Salem, Salem Co., New Jersey. 
Distribution — Southern United States, from southern New Jersey to 
the northern border of Florida, westward throughout the Gulf 
states, Tennessee and part of Kentucky, southern Illinois and 
southern Missouri to Kansas, Oklahoma and eastern Texas. 
Special characters — Readily distinguished from a Peromyscus by its 
long and more scantily haired tail, its large hind feet and decidedly 
less abrupt line of demarcation between color of sides and belly, which 
is gradual and not sharply defined, and from all other Rats or Mice 
which occur within our limits either by its size or by the arrangement 
of the tubercles on the crowns of the grinding teeth (two longitudinal 
rows). It occurs within our limits only in southern Illinois. 
Description — Middle of upper parts from head to base of tail dark 
brown shading into pale brown tinged with buffy on the sides; 
under parts grayish, the hairs grayish plumbeous at the base and 
tipped with white, but the grayish under fur showing through; 
tail very scantily haired, dark above,. pale below; feet whitish 
(pinkish white in life). 
