138 Field Museum of Natural History — Zoology, Vol. XI. 



Subgenus ICTIDOMYS Allen. 



''Ears generally small, sometimes rudimentary; tail long, cylindrical, 

 or narrow and flattened, or quite broad, with the hairs one-half to three- 

 fourths the length of the body; skull very long and narrow; first upper 

 premolar usually rather small and the dentition not heavy" (Allen). 



KEY TO OUR SPECIES. 



Back with stripes and rounded spotg. 



Striped Prairie Squirrel. Citellus tridecemlineatus, p. 138. 



Back not striped, general color grayish tinged with brown; hairs vermiculated with 



blackish. Franklin's Prairie Squirrel. Citellus franklini, p. 144. 



Citellus tridecemlineatus (Mitchill). 



Striped Prairie Squirrel. Striped Spermophile. Striped Gopher. 

 Thirteen-lined Ground Squirrel. Striped Ground Squirrel. 



Sciurus tridecem-lineatus Mitchill, Med. Repos., N. S., VI, 1821, p. 248. 



Spermophilus tridecimlineatus Lapham, Trans. Wis. State Agr. Soc, II, 1852 

 (1853), p. 339 (Wisconsin). Kennicott, Trans. 111. State Agr. Soc, I, 1853-54 

 (1855), p. 579 (Cook Co., Illinois). lb., Agr. Rept. for 1856, U. S. Patent 

 Office Rept., 1857, p. 74 (Illinois). 



Spermophilus tridecem-lineatus Miles, Rept. Geol. Surv. Mich., I, i860 (1861), 

 p. 221 (Michigan). Allen, Proc. Bost. Soc. Nat. Hist., XIII, 1869 (1871), 

 p. 189 (Iowa). Strong, Geol. Wis., Surv. 1873-79, I, 1883, p. 440 (Wisconsin). 



Spermophilus tridecemlineatus Osborn, Proc. Iowa Acad. Sci., I, 1887-89 (1890), 

 p. 43 (Iowa). Herrick, Geol. & Nat. Hist. Surv. Minn., Bull. No. 7, 1892, 

 p. 165 (Minnesota). Evermann & Butler, Proc. Ind. Acad. Sci., 1893 (1894), 

 p. 128 (Indiana). Bailey, U. S. Dept. Agr., Bull. No. 4, Ornith. & Mamm., 

 1893, p. 31. Hoy, Agr. Rept. for 1853, U. S. Patent Office Rept., II, 1854, 

 p. 68 (Wisconsin and northern Illinois). 



Citellus tridecemlineatus Jackson, Bull. Wis. Nat. Hist. Soc, VI, 1908, p. 18 (Wis- 

 consin). Ih., VIII, 1910, p. 87 (Wisconsin). Hahn, Ann. Rept. Dept. Geol. 

 & Nat. Resources Ind., 1908 (1909), p. 475 (Indiana). Wood, Bull. 111. State 

 Lab. Nat. Hist., VIII, 1910, p. 524 (Illinois). 



Type locality — Central Minnesota. 



Distribution — From southern Illinois and northern Missouri to north- 

 western Ohio, southern Michigan and central Wisconsin, extending 

 west and northwest to edge of the Great Plains and the Saskatchewan 

 Region; replaced in western Missouri by an allied form, C. /. badius. 



Description — Somewhat squirrel-like in appearance, but tail com- 

 paratively short and not bushy; back with alternating stripes of 

 whitish and dark brown, the latter with central row of rounded 

 whitish spots; under parts very pale tawny brown; middle of tail 

 mixed brown and white, like colors of the back, bordered by an inner 



