90 Bailey New Species and Subspecies of Voles. 



jecting farther back than in pinetonim ; palate often with a posterior point 

 projecting into the U-shaped interpterygoid fossa; molar series long; 

 third upper molar with three tightly closed triangles and an irregular 

 posterior loop ; first lower molar with opposite reentrant angles meeting 

 behind the anterior loop. 



Measurements. Type specimen: Total length 130; tail vertebrae 24; 

 hind foot 18. Average of five females and five males from type locality : 

 Total length 135; tail vertebne 25 ; hind foot 18.1. Skull of type : Basal 

 length 25.3; nasals 7.7; zygomatic breadth 16.5; mastoid breadth 13.4; 

 alveolar length of upper molar series 7. 



Microtus pinetorum auricularis subsp. nov. 



Type from Washington, Miss., No. ffffi cT ad., U. S. Nat. Mus., Biolog 

 ical Survey Coll. Collected May 26, 1892, by Vernon Bailey. Orig. No. 

 3649. 



General characters. Size small, about equalling pinetorum; ears very 

 large for a Pitymys and conspicuous above fur ; colors dark and rich ; fur 

 short and dense like that of pinetorum. 



Color. Upper parts dark rich chestnut darkened by dusky tipped hairs ; 

 under parts washed with paler chestnut over dark under fur ; projecting 

 tip of ear with scattered dusky hairs ; tail not bicolor, scarcely darker 

 above, like the back or slightly darker; feet dull brownish. 



Cranial characters. Skull like that of pinetorum in general form and char 

 acters, but interpterygoid fossa normally U-shaped instead of V-shaped ; 

 third upper molar with three closed triangles ; first lower molar with first 

 pair of reentrant angles meeting behind anterior loop. 



Measurement. Type: Total length 120; tail vertebrae 22; hind foot 16. 

 Skutt of type: Basal length 22.3; nasals 7 ; z>gomatic breadth 15.2; mas 

 toid breadth 12.3 ; alveolar length of molar series 6. 



