1916.] 



CYNOMYS LUDOVICIANUS LUDOVICIANUS. 



15 



central Texas (Mason County to eastern Pecos Valley) ; east to about 

 the ninety-seventh, meridian in Nebraska, Kansas, and Oklahoma; 

 west to the Rocky Mountains in central Montana, Wyoming, and 

 Colorado, and in extreme eastern New Mexico. Chiefly Upper 

 Sonoran, but also ranging into Transition and Lower Sonoran Zones. 

 Introduced colonies exist, or have been reported as formerly existing, 

 in Sac County and at Burlington, Iowa; near Monroe, Louisiana; at 

 Seneca, South Carolina; and on Nantucket Island, Massachusetts.' 



CJiaracters. — Skull with superior surface of maxiUary root of 

 zygoma bordering premaxillary and frontal bones narrow, sharply 

 emarginate anteriorly; audital buUse comparatively small. Colora- 

 tion in fresh summer coat less vinaceous-cinnamon than in Cynomys 

 ludovicianus arizonensis. 



Color. — Adult in full fresh summer pelage: Upperparts from nose to 

 between eyes, between ears, nape, and over entire body above, dark 

 pinkish cinnamon, finely lined with black and buff. Individual hairs 

 black at base, followed by buffy white, then cinnamon, with sub- 

 terminal band of buff, and, in unworn condition, narrow tip of 

 blackish. Mixed with these are numerous wholly black and half- 

 black hairs, rather longer than the ordinary pelage, the chief cause 

 of black streaking. Upper lip, sides of nose, and eye ring buff or 

 buffy white; whiskers black; cheeks and sides of head buffy or 

 vinaceous-cinnamon, with numerous blackish hairs; arms above, 

 sides of body, and legs above pale ochraceous-cinnamon; feet buffy. 

 Tail above for about two-thirds its length like back, below paler 

 vinaceous-cinnamon; terminal third chiefly black or blackish brown 

 above and below, with extreme tip of lighter blackish brown. Under- 

 parts of body from chin to near tail whitish or buffy white. Nails 

 blackish, tipped with light horn. Iris hazel. Adult in full fresh winter 

 pelage: Pelage much thicker, softer, and longer than in the summer 

 coat; less ochraceous or pinkish cinnamon, more buff and gray. 

 Upperparts grayish cinnamon (mixed pale cinnamon, whitish, and 

 black). Individual hairs intense black at bases, then pale buff, with 

 subterminal band of cinnamon and tip of almost pure white. Mixed 

 throughout this pelage, as in the summer coat, are numerous long 

 overlying hairs of black. Forehead with considerable blackish; tail 

 as in summer. Underparts dark buff or pale cinnamon, the hairs black 

 at bases, whitish midway, and broadly tipped with pale cinnamon- 

 buff. Juvenile pelage: Upperparts clear ochraceous-cinnamon, with 

 admixture of a few white and blackish hairs ; underparts whitish or 

 pale buffy yellow; tail clear ochraceous-cinnamon, broadly penciled 

 with black; bases of many of the black pencil hairs pure white. 



Both the summer and the winter coats rapidly fade and wear, and 

 the resulting variations in color are considerable. Specimens are 

 frequently greatly affected by the color of the soil, and numerous 



