58 



SECOND YARKAND MISSION. 



having the tail longer than the body, and apparently in having a shorter head and more 

 hairy ears. Another form showing considerable resemblance is G. unguiculatus x from 

 Chinese Mongolia, which, however, is represented as wanting the dusky tip to the tail, and 

 as having the tail shorter than the body. This species agrees with G. cryptorhinus in 

 having hairs on the soles of the fore-feet as well as on those of the hind, but the skull is 

 more convex above, and has the prominent lachrymal process united to the frontal. Prom 

 the other Asiatic forms there are greater differences. From G. indicus" 1 and G. persicus 3 the 

 present species is distinguished by its hairy hind-feet and shorter head ; from G. ery thrums* 

 and G. hurriance s by its very differently shaped and much longer head, its white under 

 surface, &c. ; and from G. psammophilus 6 by its much longer tail. It is, moreover, to the best 

 of my knowledge, distinguished from all the species named by the peculiar flap covering 

 the nostrils. There is certainly nothing of the kind in G. indicus, G. persicus, G. hurriance, 

 or G. nanus, nor can I find it described in any other species. 



A Gerbillus' 7 is described by Severtzoff from Western Turkestan under the name of 

 Jferiones collium. It is said to be rufescent above, white below ; the hairs of the tail rufes- 

 oent and black mixed ; the tuft at the end of the tail of two colours, fuliginous and 

 canescent ; " the black tail-tuft surrounded by a pale-grey margin." The description does 

 not agree sufficiently with the present form to render it probable that it refers to the same 

 species ; the description of the tail, and especially of the tuft at the end, shows the 

 Western Turkestan animal to be distinct, and the tail is said to be shorter than the body. 

 G. collium is, however, said to be allied to G. tamaricinus ; so it probably resembles 

 G. cryptorhinus very closely. G. opimus, G. meridianus, and G. tamaricinus are also said 

 to be found in Western Turkestan. 



Family— BIPOUIDzE. 

 39. DlPITS LAGOPUS. 



Liechtenstein in Eversman's Reise nach Buchara, p. 121. — Braudt, Bull. Ac. Imp. St. Pet., 1844, ii, p. 218. 

 1, Koshtak, South of Yarkand ; 2, Yarkand ; 3 Yangihissar. 



These specimens agree on the whole fairly with Lichtenstein's original description and 

 measurements ; the ears are rather larger, but the difference does not appear great. The 

 tarsi are also a little longer. The following is a short description : colour above light sandy- 

 brown, slightly washed with dusky ; below pure white ; a white band across the outside of 

 the thigh. Tail pale-brown above, whitish below, with a tuft of longer hair, altogether 

 about 2^ inches long ; at the end the terminal portion pure white, the proximal portion black 

 or dark-brown on the upper part and sides, but brown or white beneath the tail. The 

 fur is very soft and rather long, 0'6 to 0*8 inch in the middle of the back ; on the upper 



1 A. Milne-Edwards, Ann. Sc. Nat., Ser. 5, Vol. vii, 1867, p. 377.— Rech. Mam., p. 142, PI. Xa, XI. 



2 Hardwicke, Trans. Lin. Soc, viii, p. 279, PI. VII. 



3 W. Blanf., Eastern Persia, ii, p. 66, PI. VII, fig. 1. 



4 Gray, Ann. Mag. Nat. Hist., 1842, Ser. 1, x, p. 266 (?iec Jerdon, Mam. Ind., p. 187.) 



6 Jerdon, Mam. Ind., p. 186.— W. Blanf., Eastern Persia, ii, p. 68. 

 fi A. Milne-Edwards, Kech. Mam. p. 144. 



7 Turk. Jev., p. 83 ; Ann. Mag. Nat. Hist., July, 1876, Ser. 4, xviii, p. 55. It appears to have heen first called M, montanus> 

 but the name was changed because of there being a South African species called Gerbillus montanus. 



