No. 36. NOETH AMEEIOAH FAUNA. June, 1914. 



REVISION OF THE AMERICAN HARVEST 



MICE. 



(Genus Reithrodontomys.) 



By Arthur H. Howell. 



INTRODUCTION. 



HISTORY AND MATERIAL. 



The mice of this genus have been known to naturalists since the 

 days of Audubon and Bachman. At that time only a single species, 

 the eastern harvest mouse, was known, it having been described by 

 Bachman in 1841 under the name of Mus Jiumulis from specimens 

 collected near Charleston, S. C. The following year (1842) the same 

 authors redescribed this species as Mus lecontii from a specimen 

 collected by Maj. John Leconte in Liberty County, Ga. 



Although the species was known from only a few locahties (Geor- 

 gia, South CaroHna, and Virginia), and considered rare, its habits 

 were quite fully described by Bachman in ^'Quadrupeds of North 

 America," published in 1851. The spelling of the name was there 

 changed to '^Jiumilis.^' Even at that time Bachman appreciated 

 the fact that this species was not closely related to true Mus, as is 

 indicated by the following statement : 



In examining the teeth of this species, we have found that the tuberculous sum- 

 mits on the molars were less distinct than in those which legitimately belong to the 

 genus Mus, and that there are angular ridges on the enamel by which it approaches 

 the genus Arvicola; it is in fact an intermediate species, but in the aggregate of its 

 characteristics perhaps approaches nearest to ifws, where we for the present have 

 concluded to leave it.^ 



His keenness in noting the distinction between the molars of the 

 harvest mouse and of Mus makes his failure to mention the groov- 

 ing of the incisors all the more remarkable, but as pointed out by 

 Osgood 2 the rest of the description fits the species so well that there 



1 Aud. & Bach., Quad. N. Am., II, 1851, p. 106. 

 8 Proc. Biol. Soc. Wash., XX, 1907, pp. 49-50. 



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