28 CITELLUS. 



buff; tail above, the hairs are buff at base, then black and tipped with 

 buff; beneath, dark buff in center with marginal brownish black bands 

 and buffy white tips. Ex type in United States National Museum. 



Measurements. Total length, 194; tail, 87; hind foot, 30. Skull: 

 Occipito-nasal length, 30; Hensel, 24.2; zygomatic width, 17.3; inter- 

 temporal width, 6; length of nasals, 10.8; palatal length, 12.7; length 

 of upper molar series, 5; length of mandible, 11.2; length of lower 

 molar series, 5.2. Ex type in United States National Museum. 



Genus Citellus (52). Spermophiles. 

 Subgenus A. l Ammospermophilus. 



Citellus leucurus insularis (Nelson and Goldman). 



Ammospermophilus leucurus insularis Nels. and Goldm., Proc. Biol. 

 Soc. Wash., XXII, 1909, p. 24. 



Type locality. Espiritu Santa Island, Lower California, Mexico. 



Genl. Char. Similar to C. leucurus but larger; tail beneath grizzled 

 with black. 



Color. Top of head and upperparts of body and flanks fawn-color; 

 a white stripe on each side of back; shoulders and outer side of hind 

 legs dull fawn-color; cheeks, side of neck, lower parts of flanks whitish; 

 tail above blackish with white intermixed, and a white subterminal 

 band; beneath whitish grizzled wi h black and bordered with black. 

 Type in United States National Museum. 



Measurements. Total length, 232; tail, 77; hind foot, 36. Skull: 

 Total length, 41.8; Hensel, 32.4; zygomatic width, 24.6; intertempo- 

 ral width, 10.5; length of nasals, 12.6; length of palate, 18.6; length 

 of upper molar series, 6.4; length of mandible, 18.4; length of lower 

 molar series, 7.1. Ex type in United States National Museum. 



Subgenus C. Ictidomys. 



Citellus tridecemlineatus hollisteri Bailey. 



Citellus tridecemlineatus hollisteri Bailey, Proc. Biol. Soc. Wash., 

 XXVI, 1913, p. 131. 



Type locality. Sacramento Mountains, New Mexico. Altitude, 

 8000 feet. 



1 1 fail to find any distinctions in this subgenus or in Callospermophilus so tren- 

 chant as to require their selection from the rest of the subgenera of Citellus for full 

 specific rank. 



