284 BITLLETIN 56, UNITED STATES NATIONAL MUSEUM. 



Merriam, the western 4-striped chipmunks of the genus Entamias 

 appear to be an offshoot from the subgenus Ammospermophilns of 

 the genus C'tteMus; while the restricted Tmnias appears to have been 

 derived from Ictidomys. 



KEY TO THREE SPECIES OF THE GENUS EUTAMIAS. 



a. With five well-defined black dorsal stripes, separating four light ones. 



Eiitowias ciiicrcicollis (p. 28-i). 

 aa. Dorsal stripes obsolete or obscure. 



1). Black restricted to the middle dorsal stripe. 



Eutamias dorsalis (p. 288). 

 66. Black not restricted to the middle dorsal strijie. 



Eiitaiiiitis jurrrittDii (p. 29")). 



EUTAMIAS CINEREICOLLIS ( Allen). « 

 ARIZONA CHIPMUNK. 



Tamias clnereicollis Allen, Bull. Am. Mus. Nat. Hist, III, p. 94, .Tnne, 1890 



(original de.scription ) ; VII, 189.5. p. 24.3. 

 Eutamias einereicoJJis, Miller and Rehn, Proc. Bost. Soc. Nat. Hist., XXX, 



No. 1. Dec. 27, 1901, p. 40 (S.vst. Results Study N. Am. Mam. to close of 



1900). 

 [Taniid.^^ cinrrcicollis. Elliot. Field Col. Mus., Zool. Ser.. II, 1901, p. 75 



(Synop. Mam. N. Am.). 

 Yung-ijl-Oh of the Ilopi Indians of northeastern Arizona. 



Type-locality. — San Francisco Mountain, Arizona. (Type, skin 

 and skull, No. HIM? U. S. National Museum, Biological Survey 

 Collection.) 



Geographieal range. — Boreal zone of mountains of the Colorado 

 Plateau, in northeastern Arizona. 



Description. — Size medium ; pelage full and soft ; ears medium 

 size; dorsal surface with five plainly defined dark stripes and four 

 light ones of about equal breadth. The original description, by Dr. 

 J. A. Allen, based in part on our collection, reads as follows: 



AiitumnaJ pelage (August and September). — General color above gray; sides 

 between shoulders and hips yellowish brown ; below grayish white ; nape, sides 



1 .Mr. Vernon Bailey has described the following sulispecies : 



Eutaniias ciiiereicollis canipes Bailey, Pi'oc. Biol. Soc. Washington, XV, 

 p. 117. June 2, 1902. 



Tiipe-locaUty. — Gaudalupe Mountains, El Paso County, Texas. Altitude 7,000 

 feet. Type, Cat. No. 109229, U.S.N.M. 



Oeneral characters. — Similar to cinereicolUs in fresh postbreeding pelage, but 

 grayer throughout, with paler .nd duller ochraceous on sides; tips of the long 

 hairs on rump and upper surface of tail white instead of yellowish ; feet clear 

 gray without, a tinge of yellowish ; black dorsal stripe reaching forward to 

 between ears. 



Measurements. — Type: Total length 230 mm.; tail vertebr?e 104; hind foot 3.5. 

 ^kitU of type: Basal length 30; nasals 11; zygomatic breadth 19.3; mastoid 

 breadth 1,5.8; alveolar length of upper molar series 5.8. (Proc. Biol. Soc, Wash., 

 XY,p. 117.) 



