ALTICOLA 319 



Skull rather lighter and narrower than in A. roylei and A. 

 montosa. Anterior palatal foramina short and broad, terminating 

 considerably in advance of the tooth-rows. Cheek-teeth small 

 and light, the capsule of ni^ not obstructing the mouth of the 

 sphenorbital fissure. Auditory bullae large and globular, much 

 larger than in A. roylei though less inflated than in A. phasma, 

 and somewhat deeper though not quite so wide as in A. montosa. 



Cheek-teeth : m^ with three well-developed salient angles on 

 each side ; its posterior loop shut off from the third triangle, 

 usually rather long and bearing more or less evident vestigial 

 traces of the fourth and fifth outer and the fourth inner salient 

 angles (Fig. 91, 4-7, lo). 



Enamel of incisors yellow, the tint deeper than in A. roylei. 



Remarks. — Three subspecies are at present recognized, viz., 

 the typical form A. w. worthingtoni, described from the Thian- 

 Shan Mountains, characterized by its pure white under parts 

 and white tail and feet ; A.w. subluteus, described from Djarkent, 

 distinguished by the pale pinkish-buff tinge which pervades 

 its under parts, feet and tail ; and the recently described A. w. 

 semicanus from Central Mongolia, a form with buffy under parts 

 and larger skull. 



9a. Alticola worthingtoni worthingtoni Miller. 

 1906. Alticola worthingtoni Miller, Ann. Mag. N.H., [7], 17, p. 372. 



Type.—B.M.., No. 5.12.4.11; adult female, skin and skull, 

 collected Sept. 30, 1904, by A. B. Bayley Worthington. 



Type locality. — Thian-Shan Mountains (Koksu). Altitude 

 9000 feet. 



Characters. — Essential external characters, skull and teeth as 

 described above under the species. Under parts pure white. 



Colour of upper parts finely blended smoke grey and black, 

 with a faint suffusion of pale ochraceous buff, particularly on the 

 sides. The individual hairs are blackish-slate throughout the 

 greater part of their length, then smoke grey darkening to 

 ochraceous, which is succeeded by a blackish tip. Under parts 

 white, the dark bases of the hairs appearing irregularly at the 

 surface. Feet white, with a faint creamy tinge. Tail light 

 cream-buff, with a faint brownish tinge in the pencil. 



For external and cranial measurements, see tables at end of 

 volume. 



9h. Alticola worthingtoni subluteus Thomas. 

 1914. Alticola xcorthiiujloni subluteus Thomas, Ann. Mag. N.H., [8], 

 13, p. 570. 



Type.—B.M., No. 14.5.10.186; slightly immature female, 

 skin and skull, collected July 20, 1913, by W. Riickbeil. 



Type locality. — Djarkent, Semiretschensk, Central Asia (" In 

 die Schlucht Tischkan "). 



