1903.] NATURAL SCIKN-CES OF PHILADELPHIA. 19 



upper surface of the feet. Tail above centrally rich ferruginous, most 

 intense basally, lateral fringe with the basal portion of the hairs black, 

 the apical section pale ochraceous, the black becoming more extensive 

 toward the apex of the tail and forming an almost clear black bar about 

 20 mm. in length, the extreme tip being formed by the pale ochraceous 

 tips of the hair. Lower surface of the tail pale grayish ochraceous, the 

 successive black and ochraceous color divisions being marked as above ; 

 toward the apex of the tail a trace of the upper color is noticed suffusing 

 the grayish ochraceous portion. Under surface, including the lips, 

 chin, throat, under surface of the limbs and feet, whitish, pure on the 

 throat, mixed elsewhere with the tint of the pale mouse-colored 

 under fur. 



Skull. — The skull of S. fremonti hjchnuchus differs from that of S. 

 fremonti neomexicanus in its more elongate form and slender and more 

 attenuate nasals. The skull of hjchnuchus is comparatively narrower 

 than that of neomexicanus, and the zygomatic region appears com- 

 pressed. The nasals average 1.7 mm. longer in lychnuchus than in 

 neomexicanus,, while they really average narrower in width by .2 mm. 



Measurements. — Flesh dimensions of the type: Total length, 350 

 mm.; length of tail, 140; length of hind foot, 55. Average of three 

 specimens (flesh measurements) : Total length, 335 (326-350) ; length of 

 tail, 140; length of hind foot, 53.3 (51-55). Average of seven speci- 

 mens of S. fremonti neomexicanus:^ Total length, 321 (308-330) ; length 

 of tail, 133 (127-145) ; length of hind foot, 48.5 (45-52). 



The type skull of lychnuchus measures as follows: Total length, 

 50 mm.; basilar length, 42; greatest zygomatic width, 29; length of 

 nasals, 16; width of nasals, 8.2. The average of six skulls of the new 

 form is : Total length, 49 (48-51) ; basilar length, 40.9 (40-42.2) ; greatest 

 zygomatic width, 27.9 (27-29); length of nasals, 15.7 (15.5-16) ; width 

 of nasals, 7.4 (7-8.2). Average of four skulls of neomexicanus:'' Total 

 length, 45.9 (43.5-47.3); length of nasals, 14.3 (13.7-15). The. two 

 skulls of topotypes of neomexicanus examined by us give the follow- 

 ing measurements : Total length, 46.7 (46.5-47); basilar length, 39.7 

 (39-40.5); greatest zygomatic width, 27.7 (27-28.5); length of nasals, 

 14; width of nasals, 7.6 (7.5-7.7). 



Specimens Examined. — Four skins from the type locality, Rio Rui- 

 doso and Mescalero, all in the White Mountains. One of the skins and 

 three additional skulls were from the collection of the American 

 Museum of Natural History. 



2 Allen, Bull. Amer. Mus. Nat. Hist., X, p. 291. 

 •' Ibid. 



