Descriptions of EigJd Neiv Pocket Gophers. 215 



Color. — -Upper parts from half way between ej^es and nose posteriorly to 

 tail, russet fulvous ; under parts dark plumbeous, washed with salmon 

 fulvous; nose, muzzle all round, and ear spot dusky ; fore and hind feet 

 and tail wiiitish, irregularly clouded with dusky. 



<'nt)tinlclt(ir(ict('rx. — Skull short and broad; zygomata abruptly and 

 widely spreading, with anterior-external angle nearly square and jugals 

 parallel; nasals rather short, broad, squarely truncate posteriorly, and 

 early ankylosed together ; temporal ridges distant, parallel ; interparietal 

 ratlier large and roughly oval ; audital l)ulUe rather large; u])per incisors 

 not sloping forward. 



^feasurement.9. — Type specimen: total length, 220; tail vertel)ne, 07; 

 hiud foot, 29. Average of 6 specimens from type locality: total length, 

 20o; tail vertebra?, 64; hind foot, 27. 



Thomoniys leucodon sp. nov. 



Tjipe froui Grant Pass, Rogue River Valley, Oregon. No. Ifstf, cJ* ad. 

 U. S. Nat. Mus., liiological Survey Coll. Collected Dec. 17, 1891, by C. 

 P. Streator. Original No. 1394. 



General clutracters. — Similar to T. lat!eep>s from Humboldt Bay, but 

 smaller ; under parts brighter fulvous ; incisors white instead of yellow 

 and sloping more strongly f(jrward ; all the teeth much smaller. 



Color. — Upi>er {)arts from nose to tail dull fidvous brown, becoming 

 brighter on sides and belly; nose, sides of mouth, and ear spots dusky 

 [no dusky ring round eye] ; fore and hind feet whitish; tail yellowish 

 buff. 



Crroi hd and denial chnracten^. — Braincase 1 )road ; zygomata widely spread- 

 ing; temporal ridges parallel, distant ; interparietal rather large, shield 

 shaped ; skull similar to that of 2\ laticeps but smaller ; nasals narrower 

 and more deeply notched posteriorly ; basi-occipital narrower ; incisors 

 sloping far forward, their anterior faces white (sometimes slightly stained 

 with i)ale yellow), narrower and more rounded than in hdicep:^. 



Mensnronents. — Type specimen : total length, 221; tail vertebrae, 68 ; 

 hind foot, 29. 



Thomomys opeiarius sp. nov. 



Tijpeh'om Iveeler, Owens Lake, luyo Co., California. No. ll\lt, (J ad. 

 U. S. Nat. Mus., Biological Survey Coll. Collected Nov. 29, 1890, by 

 E. W. Nelson. Original No. 1. 



General characters. — Size small ; color pale buffy ; fore claws very long 

 and slender; cranial characters peculiar. Does not require comparison 

 with any known species. 



Color. — Uniform buffy yellowish or buff gray (according to pelage) from 

 end of nose to tail ; post-auricular spots plumbeous; under parts plum- 

 beous strongly washed with white ; fore and hind feet and tail white. 



Cranial characters. — Skull short, broad, and massive, with widel}^ and 

 S(iuarel3' s])reading zygomata, short and broad rostrum, broad interorbital 

 region, and well marked temporal ridges (1-2 mm. apart in adults). 



