8 
SECOND YARKAND MISSION. 
I liaye not overlooked the fact mentioned by Dr. Gunther in the “Reptiles of British 
India,” 1 2 * * * * * and to which reference has already been made, that specimens from Tibet had been 
compared by Professor Peters of Berlin with typical examples of L. caudivolvula , and found 
specifically identical. I confess that it appears at the first glance as if the opinion of so high 
an authority on the Reptilia as Professor Peters must he more correct than mine, hut I think 
there must be some mistake, as I have already indicated when noticing the description ° 
P. caudivolvulus by D inner il and Bibron. The original types of Pallas can scarcely he m 
Berlin, and it has frequently happened that other species have been sent from Russia under 
Pallas’ names. Under any circumstances I cannot hut think, for the reasons given above, that 
Pallas must have described a different lizard. 
Steindachner in his description of P. stoliczkce, -which is certainly the same lizard as 
P. theobaldi, several of the specimens examined by Steindachner being from the typ ica 
locality of the last-named species, points out that P. stoUczhce differs from P. caudivolvula 8 
in its shorter tail and in having smooth scales on the upper surface of the limbs. The latter 
character, however, is not constant. Keels may generally he detected in P. theobaldi on the 
scales of the tarsus, and not unfrequently on the thigh and forearm, and in the Turkestan 
variety, P. forsythi, they are the rule. The length of the tail is, however, a characteristic 
distinction, though, I believe, it is not the only one. 
It is only after long and repeated comparison that I have come to the conclusion, tha 
P. forsythi of Anderson cannot he separated from P. theobaldi? At the first glance > 
they appear distinguished by colour and by the Turkestan form having some scattered, whnis > 
enlarged scales on the hack, and keels on the scales covering the upper surface of the limbs- 
Individuals, however, vary greatly in the scales of the hack ; in some these are convex an 
granular, in others flat, smooth, and even suhimhricate ; in some larger in the middle of t i e 
hack, in others nearly the same size throughout. The scales on the top of the head are 
scarcely alike in any two individuals ; some have the scales large on the occiput and xeiy 
small on the supra-orhital region, in others all are of about equal size ; in some the enlarge 
superciliary scales almost reach the nasals, in others three or four small scales intervene- 
The keels on the limb scales and the enlarged scales on the sides of the hack are no m° re 
constant than the other characters. I find specimens from Western Tibet with a te 
scattered enlarged scales, and with distinct keels on the limb-scales, and I find specimens 
Eastern Turkestan in which the enlarged scales are wanting and the keels can scare j 
he detected. . g 
Even in colouration, I do not think the difference, although it is usually marked, 
constant. P. forsythi has almost always a row of rather distant dark spots, arranged iu P air 
down each side of the back. These spots consist of rather pointed scales. P. l' ie0 
jbcikti 
varies exceedingly in colour. Some specimens, perhaps the most, are rather irregu ar 
spotted, others have large ocelli on the hack ; in others again there are no markings wha 
But there is very often a tendency to a double row of spots down the hack, and m 
cases a very near approach to the colouration of P. forsythi, and in the latter the sp 
1 P' 161- _ _ _ . f p theolatt* 
2 I may here remark that I believe Dr. Anderson was misled by his collectors into supposing that the specimens 01 by 
described by him, Proc. Zool. Soc., 1872, p. 387, underthe name of P. caudivolvulus, were from Yarkand. Dike the gecko n ^ ^ 
him Cyrtodadylus yarTcandensis, I think it almost certain that the Phrynocephali in question must have been co ee ^he 
Upper Indus valley, in Ladak. Every specimen from Yarkand and Eastern Turkestan in Dr. Stoliczka’s large collection ^ ^ ojn 
colouration of P. forsythi, whilst the specimens described by Dr. Anderson, which I have examined, are uudistinguis 
some of those procured by Dr. Stoliczka in Ladak. 
