RODENTIA : MURID.E. 99 



ern Europe and Asia, differs from rats in having cheek- 

 pouches and a hairy tail. 



b. Sigmodontes, or New-World Rats and Mice, are 

 characterized by narrower molars than in Mures, and 

 those of the upper jaw have two tubercles in each, trans- 

 verse series. 



The Genus Reithrodon Harvest Mice is charac- 

 terized by short, hairy ears and tail, and upper incisors 

 with a longitudinal channel along the anterior face. 

 There are four species in the United States. 



The Harvest Mouse, R. humilis, Baird, of South Carolina 

 and westward, is less than two inches and a half long to 

 the tail, which is a little shorter than the head and body ; 

 the color above grayish-brown, grayish-white beneath. 

 The region about the mouth, and the chin, and feet are 

 white. 



The Long-tailed Harvest Mouse, R. longicauda, Baird, 

 of California, is very similar to R. humilis. 



The Genus Hesperomys White-footed Mice is char- 

 acterized by a murine appearance, variable and scantily- 

 haired tail, molars diminishing from first to last, and 

 elongated, the sides indented and the crowns with a sin- 

 gle longitudinal furrow. Most of the species have white 

 feet, and the tail whitish with a darker stripe above. 

 Fifteen or more species inhabit the United States. 



The White-footed, or Deer Mouse, H. leucopus, Wagner, 

 of Labrador to Virginia 



Flff 



and westward to the Mis- 

 sissippi, is three to four 

 inches long to the tail, 

 which is nearly as long as 

 the head and body ; the col- 



J White-footed Mouse, H. leucopus, Wagner. 



or yellowish -brown, with 



generally a dorsal wash of darker, and the under surface 



of the tail pure white. 



