Descriptions of Six New Ground Squirrels. 71 



of belly; feet soiled whitish; tail grayer and l^ss fulvous than in mollis. 

 Young similar to young of mollis, but decidedly darker; head and neck 

 pale dull-fulvous instead of buffy-ochraceous ; tail strikingly shorter and 

 darker. 



Cranial characters. Skull similar to that of mollis, but shorter and rela 

 tively broader ; rostrum conspicuously shorter ; molariform teeth smaller 

 (tooth row 1 mm. shorter) ; nasals shorter but variable, usually ending 

 behind plane of premaxillse. 



Measurements. Type specimen : Total length 198 ; tail vertebrae 38 ; hind 

 foot 30. Average of 3 specimens from type locality : Total length 194.3 ; 

 tail vertebrae 40; hind foot 30.3. 



Spermophilus tridecemlineatus alleui* subsp. nov. 



Type from Bighorn Mts., Wyoming. No. 56050, tf, U. S. Nat. Mus., 

 Biological Survey Coll., Sept. 18, 1893. Collected by Vernon Bailey. 

 Original No. 4383. 



Characters. Size small (nearly as small as parvas) ; ground color of 

 upper parts fully as dark as in typical tridecemlineatus; light spots in 

 dorsal rows relatively larger and tail darker and much less reddish than 

 in tridecemlineatus. 



Cranial characters. Skull and teeth similar to those of parvus (perhaps 

 very slightly larger), but audital bullse very much smaller. 



Measurements. Type specimen : Total length 211 ; tail vertebrae 74 ; 

 hind foot 32. . 



Spermophilus tridecemlineatus texensis subsp. nov. 



Type from Gainesville, Cooke Co., Texas. No. |^|, c? ad., Merriam 

 collection, April 15, 1886. Collected by G. H. Ragsdale. 



Characters. Similar to S. tridecemlineatus, but smaller; ground color of 

 upper parts, including base of tail, redder; middle stripe of under side of 

 tail uniform deep reddish, not grizzled with black ; no ye41o wish-olive 

 tinge in any pelage and less seasonal 'difference in color than in any of 

 the other forms. 



Color. Winter pelac/e : Ground color of upper parts, including base of 

 tail, rich deep ferruginous or rusty, slightly grizzled with black hairs ; 

 nose grayish, slightly grizzled with rusty ; sides of neck, feet, and under 

 parts huffy; head niarblings, dorsal stripes and spots, chin and lips 

 buffy-white ; rusty under side of tail sometimes partly hidden by buffy 

 tips. Summer pelage : Similar to winter pelage, but ground color duller 

 and light stripes and spots more buffy. 



* In honor of Dr. J. A. Allen, who first defined and named the sub- 

 genus Ictidomys to which the tridecemlineatus group belongs, and to whom 

 we are indebted for its two best marked members pallidus and parvus. 



