CYNOMYS. 155 
Genl. Char. Size large; tail nearly twice as long as that of C. 
gunnisont. 
Color. Summer Pelage. Above vinaceous cinnamon; below whit- 
ish; tail with a narrow subterminal bar of broccoli brown. 
Winter Pelage. Above pale sandy buff; below white tinged with 
buff. 
Measurements. Total length, 376; tail vertebre, 84; hind 
foot, 61. Skull: basilar length, 54.3; total length, 66; interorbital 
width, 14; length of nasals, 25; zygomatic width, 43.5; length of 
upper molar series, 16.3. 
Fic. XXXII. CYNOMYS LUDOVICIANUS. PRAIRIE-DOG. 
115. ludovicianus (Arctomys), Ord, Guth., Geog., 11, 1815, 2d Am. 
ed., p. 292. 
soctalis Rafin., Am. Month. Mag., 11, 1817, p. 45. 
grisea Rafin., Am. Month. Mag., 11, 1817, p. 45. 
missouriensis Warden, Descrip. Etats Unis, v, 1820, p. 627. 
latrans Harlan, Faun. Am., 1825, p. 306. 
ludovicianus (Cynomys) Elliot, Syn. N. Am. Mamm., 1901, p. 102. 
PRAIRIE-DOG, Perrito, Perrito del Campo, in Mexico. 
Type locality. Plains of the Upper Missouri. 
Geogr. Distr. State of Chihuahua, Mexico, north into western 
Texas and Kansas to 49th parallel. 
Genl. Char. Body stout; tail short; ears very small; claws long. 
