Gfiil. Char. Similar to G. brivUeps, but smaller. Skull similar 

 to that of G. bririceps, but relatively smaller in its various parts. 



Ci'h'r. Above russet brown tinged with fulvous; dusky on median 

 line; nose and head almost black tinged with fulvous; interior of 

 pouches, chin, throat and fore legs, white. 



Measurements. Total length, 225: tail vertebra', 70; hind foot, 27. 



b.—attwateri. {Gecnivs), Merr. , Mon. Geom., N. Am. Faun., No. 8, 

 1895, p. 135. 



Tvpe localUy. Rockport, Arkansas County, Texas. 



Geogr. Distr. Coast and islands of Texas between Matagorda 

 and Nueces Bay; also in interior, and vicinity of San Antonio. 



Gcnl. Char. Similar to G. bririceps, but larger and not so dark. 

 Skull: zygomata strongly divergent anteriorly, angular, depressed; 

 nasals narrow posteriorly; premaxilla? broad. 



Ci>/or. Above russet brown, dusky on head and median dorsal 

 line; beneath ranging from whitish to buffy ochraceous. Sometimes 

 the head from nose to occiput is black. 



M,;!s:iremen/s. Total length, 250; tail vertebra-, 85; hind foot, 30. 



325. texensis. {Geomvs), Merr., Mon. Geom., N. Amer. Faun., No. 



8, 1895, p. 137. 



Type localitv. Mason, Mason County, Texas. 



Geogr. Distr. Central Texas, probably south to the Rio Grande. 



Genl. Char. Size very small; tail short, apical portion naked. 

 Skull: nasals short, broad posteriorly and sides nearly parallel and 

 truncate posteriorly; nasal branches of premaxilhc reach or pass the 

 plane of orbital fossa, and are pointed; jugal shorter than basioccip- 

 ital; occiput bulging posteriorly. 



Color. Above liver brown mixed with black. Feet and under 

 parts white; base of hairs beneath are plumbeous in winter, white in 

 summer; throat with a collar of buffy fulvous. 



Measurements. Total length, 203; tail vertebra, 60; hind foot, 28. 



326. arenarius. {Geom\s), Merr., Mon. Geom., N. .\m. Faun., No. 



8, 1895, p. 139. 



Type localitw El Paso, Texas. 



Geogr. Distr. Valley of upper Rio Grande from El Paso and 

 Juarez, Chihuahua, Mexico, north to Las Cruces and west to Dem- 

 ing, New Mexico. 



Gen/. Char. Size medium, tail long, well haired, except tip, 

 colors pale. Skull: no sagittal crest; prominent knob at distal end 

 of squamosal arm of zygoma; interparietal truncate posteriorly on 

 plane of lambdoid suture; occiput moderately bulging. 



Measurements. Total length, 258; tail vertebra-, 88; hind foot, 33. 



