110 ^frrnam — T^cir Sprrieft of Tltomomiit^. 



Crariidl rharai'ttrx. — Zygomata stnuiwly spreadinu'. broader hfliind than 

 in front, willi woll developed anterior angle: temporal impressions 

 marked: interparietal subqnadrate becoming subtriangular in old age: 

 nasals narrowly cuneate, notched behind, and falling well short of pre- 

 maxilliP: bulhe medium: under jaw very long, the postcoronoid notch 

 narrow and completely covered by coronoid process. From hailryi, its 

 nearest known relative, it may be distinguished by narrower nasals, nar- 

 rower interorbital region, strikingly narrower and ilitferently shaped 

 postcoronoid notch, and less [irolruding upper incisors. 



Meaniirementg. — Type .specimen (9 ad.); total length ]!)6; tail verte- 

 bra^ 60: hind foot 28. An adult male from type locality: total length 

 207; tail vertebne .■)!): hind foot 28.."). 



Thomomys cabezonee sp. nov. 



Tjipi' from ('ai)ezon, S;in (iorgonio Pass. ( 'nlifoi'nia. No. .■):i.987. $ 

 ad., 1'. S. National .Museum, iiiological Sui-\ey ( "ollccl ion. .lune ?,. 

 18!):!. ('. 1>. Streator. Original No. 2!I0(;. 



dianirfirs. — Size medium, but smaller than iiri'iiiillithix or iniri'ux; 

 ears rather large: tail long: color \arying from bully ochraceous (as in 

 i/i/rf'iis) to dull salmon brown. 



('(ilov. — Upperparls bufly ochraceous. butfy gray, or even (in the type 

 and darkest specimen of I from type locality) dull drab-brown on back, 

 becoming butly ochraceous on sides: nose, lips, chin and opening of 

 cheek pouches dusky; uiulerparls varying from whitish to pale salmon. 



Vroiiial rhdiutrtcrs. — Skull small, angular: zygomata moderately 

 spreading, broadest anierioi'ly and sharply angular in adults: temporal 

 ridges marked: interpariclal rectangular, broader than long in immature 

 skulls: nasals long, with straight sides (not constricted), notched behind, 

 and not reaching near tips of prema.viihe: bulht^ medium. Compared 

 Avith (uiniix Aiul pt'rjxilluli/M the skull and jaw are strikingly smaller and 

 lighter, the inlerparielal (|uadrangnlar instead of s\d)-l riangidar, the 

 bulhe \-ery much smaller. Comjiared \\\\\\ jurjHilUdiix the zygomata ai-e 

 much less siireading. 



Measiirementx. — Type specimen {$ ad.): total length 2:!."): tail verte- 

 brae 79; hind fool '.W. .\verage of 7 adults from type locality: total 

 length 222: tail \erlel>r;e 7S: hind foot :{0. 



Thomomys aureus pervagus sid)sp. nov. 



Typi' from Espanola. New Mexico. No. .")8.2ilH, $ ad.. V . S. National 

 Museum, Hiological Survey Collecl ion. Janiuiry 4, 18!>1. .1. Alden Lor- 

 ing. Original No. \'AH. 



Char<trifrx. — Similar to (i/irciix but much darker, color che.stnut ful- 

 vous instead of golden fulvous: upperpai'ls dull chestnut fuhous, the 

 middle par't of l)aci< broadly uiLvcmI with black-tipped hairs: nose and 



