Descriptions of Six Nciv Rodents. 21 



Aplodontia major rainieri snbsp. iiov. 



Type from Paradise Creek, south side Mt. Rainier, Washington (alt., 

 5200 ft.). No 90144 S" ad. U. S. Nat. Mns., Biological Survey Coll. Col. 

 lected August 6, 1897, by Vernon Bailey. Orig. No. 6122. 



Characters. — 'f^hwW&.x to A. major but paler and grayer throughout, par- 

 ticularly the underparts and region around mouth ; whiskers mainly 

 white instead of black ; audital tubes smaller; incisive foramina shorter 

 and slightly more open; basioccipital notch shallower; jugal narrower 

 and more slender throughout. 



Measurevtenis. — Type specimen : Total length 375 ; tail vertebrae 33 ; 

 hind foot 62. 



Thomomys melanops sp. nov. 



Type from timberline at head of Soleduc River, Olympic Mts., Washing- 

 ton. No. 90630 ? ad. U. S. Nat. Mus., Biological Survey Coll. Col- 

 lected Aug. 28, 1897, by Vernon Bailey. Orig. No. 6219. 



Characters. — Size small ; coloration as in T. mazama — nose, space round 

 eye and large postauricular patch (eml)racing ear) slate black in strong 

 contrast to dull chestnut of upper parts ; under parts dark ])lumbeous, 

 washed with buffy fulvous ; feet and wrists white. T. douyJasl from the 

 north side of the Columbia River has the entire head reddish chestnut 

 concolor with the back, but in cranial characters agrees best with the 

 present species. 



Cranial characters. — Skull similar to that of douglasi but smaller ; inter, 

 parietal shorter posteriorly, barely notching supraoccipital ; mastoid 

 bullfe smaller: basioccipital less excavated by audital bullfe; anterior 

 root of zygoma (seen from above) broader and more squarely truncate, 

 infringing more on frontals. 



Measurements. — Type specimen: Total length 206; tail vertebrae 63; 

 hind foot 27. 



Thomomys douglasi yelmensis subsp. nov. 



Type from Tenino, Yelm Prairie, Washington. No. fif If (J ad. U. S. 

 Nat. Mus., Biological Survey Coll. Collected Oct. 24, 1891, by C. P. 

 Streator. Orig. No. 1385. 



Characters. — Similar to 2\ dovglasi but very nuich paler; face with the 

 dark markings of the mountain species. 



Cranial cliaracters. — Skull like that of douglasi but interparietal larger; 

 frontals depressed interorbitally ; angle of mandible standing out farther 

 and projecting antei'iorly so as to form a distinct hook ; incisors broader 

 and thicker. 



3Ieasurernenls. — Type specimen : Total length 222 ; tail vertebrae 68 ; 

 hind foot 32. 



