118 Bailey — New Mammals from Western Texas. 



Spermophilus spilosoma marginatus subsp. nov. 



Type from Alpine, Texas, No. 108,927, U. S. National Museum, Biolog- 

 ical Survey Collection, $ ad. Collected July 5, 1901, by Vernon 

 Bailey. Original No. 7702. 



General characters. — Similar to the dark, typical form of sinlosoma from 

 northeastern Mexico, but smaller and brighter colored. 



Color. — Upperparts bright cinnamon brown, the whole back from ears 

 spotted with whitish, the spots conspicuously edged with black. 



Skull. — With relatively small bullae and wide basioccipital. 



Measurements. — Type: total length 225; tail vertebrae 67; hind foot 32. 

 Skull of type: basal length 33.7; nasals 13.3; zygomatic breadth 23.5; 

 mastoid breadth 19; alveolar length of upper molar series 7.2. 



Specimens examined. — Alpine 1; Toyahvale 1; Presidio Co. 1 (im). 



Remarks. — From the El Paso form, marginatus differs in darker color 

 and heavier spotting; from major in finer, sharper spotting, and from 

 both in the black edging of spots as well as in cranial characters. 



Spermophiius spilosoma arens subsp. nov. 



Type from El Paso, Texas, No. 64,977, U. S. National Museum, Biolog- 

 ical Survey Collection, $ ad. Collected May 10, 1894, by Dr. A. K. 

 Fisher. Original No. 1446. 



General characters. — Similar to cryptospilotus but larger with coarser 

 spotting. 



Color. — Upperparts light clay color or dark buffy, finely spotted over 

 back and rump with white, the spots without black edges. Distin- 

 guished from neighboring forms by its pale colors. 



Skull. — Like that of cry'ptos])ilotus but more elongated, with wider 

 nasals and heavier dentition. 



Mersurements. — Type: total length 237; tail vertebras 85; hind foot 35. 

 Average of 5 adults: 230; 78; 34. Skull of tyi^e: basal length 33; nasals 

 12; zygomatic breadth 22; mastoid breadth 18; alveolar length of upper 

 molar series 7. 



Specimens examined. — El Paso, Texas, 5; Casas Grandes, Chihuahua 4. 



Microtus mexicanus guadalupensis subsp. nov. 



Type from Guadalupe Mts., Texas, altitude 7,800 feet. No. 109,191, 

 U. S. National Museum, Biological Survey Collection, $ ad. Col- 

 lected August 21, 1901 by Vernon Bailey. Original No. 7807. 



General characters. — Slightly larger and lighter colored than mexicanus, 

 with skull characters distinguishing it from both mexicanus and mogollo- 

 nensis. 



Color. — Upperparts dull umber brown; belly buffy gray; feet and tail 

 brownish gray. Scarcely distinguishable from moytdlonensis in color. 



