506 



REPORT OF STATE GEOLOGIST. 



MICROTUS PENNSYLVANICUS (Ord.). 



COMMON VOLE; MEADOW MOUSE. 



Mils pennsylv aniens Ord., Guthrie's Geog., 2d Amer. Ed., Vol. 



II, p. 292, 1815. 



Arvicola pennsylv aniens Evermann and Butler, Free. Ind. 



Acad. Sci. for 1893, p. 127. 

 Mierotus pennsylvanieus Bailey, N. A. Fauna, No. 17, p. 16, 



Diagnostic characters. — This species is distinguished from the 

 other voles found in Indiana by its long tail. It is also of a darker 

 brown color than any other species except pinetorum. The latter 

 species has soft, dense fur and tail less than one inch in length. 



Description. — The color of the back is dull dark chestnut, duller 

 in winter than summer ; under surface silvery gray Avith more 

 or less of a brown tinge in some individuals; tail and feet about 

 the color of the back or a little paler. The ear is distinctly visible 

 above the fur, but low and rounded as compared with the white- 

 footed and house mice ; eyes small and bead-like ; fur long and 

 coarse. 



Fig. 8. — Crowns of the molar teeth of Mierotus : a, Mierotus pennsylvanieus ; 

 b, Mierotus pinetorum ; c, Mierotus ochrogaster. After Bailey. North Ameriean 

 Fauna No. 17, Bureau of the Biol. Surv., U. S. Dept. of Agri. 



Measurements. — Ten specimens average: total length, 160 mm. 

 (6 6/16 in.) ; tail, 42.3 mm. (1 12/16 in.) ; hind foot, 19.8 mm. 

 (12/16 in.) ; greatest length of skull, 28 mm. 



Skull and teeth. — The skull (fig. 9) is long and rather slender, 

 but with widely spreading zygomatic arches ; incisor teeth long, 

 slender, light yellowish brown, projecting well beyond the skull 

 proper. First lower molar (fig. 8a) with an anterior, foliated loop, 

 a posterior transverse loop, and five closed triangles between them. 



Range. — From the Atlantic coast to Dakota and from Canada 

 south to th'' Carol inas. Its range, therefore, includes all of this 

 State, but it can not bt; found in every locality. P]vermann and 

 l-Jntlcr I'ccord it from Frank'lin. Carroll, Wayne, Vigo and Kan- 



1900. 



b 



c 



