SQUIRRELS OF MEXICO AND CENTRAL AMERICA 93 



SCIURUS NAYARITENSIS Allen. Nayarit Squirrel. 



Scinrus alskmi Allen, Bull. Am. Mus. Nat. Hist., N. Y., 11, pp. 167-170, 



October, 1889 (Not S. alsioJii And&rson, 1878). 

 Sciurus nayaritensis Allen, Bull. Am. Mus. Nat. Hist., N. Y., 11, p. vii, 



footnote, Feb. 1890 (new name for S. ahtoni Allen); Ibid., iii, p. 



185, 1890; Ibid., V, p. 30, April, 1893. 



Type locality. — Sierra Valparaiso, Zacatecas, Mexico. Type no. 

 1985 American Museum of Natural History, New York. 



Distributio7i. — Pine and oak forests of the Transition Zone in the 

 Sierra Madre and outlying spurs of western Zacatecas, southern Du- 

 rango, eastern Tepic and southern Jalisco, Mexico (alt. 6500-9000 ft.) . 



Characters. — Size large ; back dark gray ; ears rusty, belly and feet 

 white. Tail bushy; ears thinly haired; pelage thick and soft; under 

 fur long. Teats : p. i a. |^ i. \. 



Color. — Upperparts dark gray, with underlying rusty yellowish 

 showing through ; broad ring around eye white ; rest of sides of head 

 gray, frequently shaded with rusty brown ; ears varying from dingy 

 grayish to dull rusty brown ; outside of fore legs varying from white to 

 grayish white, or white suffused with buffy ; fore feet dingy white often 

 suffused with buffy ; outside of hind legs paler or more washed with 

 whitish than back ; hind feet grayish white, often washed with buffy ; 

 toes whitish suffused more or less with buffy ; underparts white ; tail 

 above at base like back, rest of upper surface black heavily washed with 

 white ; below, with broad ferruginous median area, heavy black border, 

 and broad white edge, the white often extending as a wash over the 

 entire lower surface. Hairs on back rusty yellow (sometimes ferru- 

 ginous) with broad subterminal black rings and narrow white tips. 



Variation. — Among 17 winter specimens from the type locality 10 

 have a more or less strong wash of rusty on the back part of crown and 

 nape — thus forming a poorly defined nape patch ; and one has a simi- 

 lar rusty wash along middle of lumbar region. This winter series is 

 more whitish on the back than summer specimens from the Nayarit 

 Mts. at Santa Teresa, Tepic ; and a series taken in September near Pla- 

 teado, Zacatecas, agrees with the one from Santa Teresa. These 

 summer skins have numerous scattered hairs on the back entirely 

 black ; others rusty yellow, or dull rufous, with sub-basal and subter- 

 minal black rings, with or without white tips ; the white tips when 

 present generally smaller than in the Valparaiso specimens. The re- 

 sult is a generally darker, more rusty, back and an increase of buffy or 

 rusty buff on feet and outside of fore legs. The surface of the tail has 

 less white and the ferruginous median area below is consequently more 



