1S72.] F. Stoliczka — On Indian Lizards. 87 



In connexion with the descriptive details, (often necessarily tedious), I 

 have noted the geographical distribution of most of the species, as far as I 

 had been able to obtain reliable information. 



Fam. LACJEBTIDJE. 



From observations which I made on Tachydromus, Opfiiops, and Aean- 

 tlwdactyhis, I presume that the form, size and number of shields on the 

 antero-superior part of the head, and also partially the nasal shields are un- 

 reliable for generic, and often even for specific, distinctions. 



Tachtdromus sexlineatus (I. E., # p. 69.) 



I have from the low valleys of Sikkim 25 specimens which I believe 

 to be Daudin's T. sexlineatus ; they certainly belong to the same species 

 which occurs in Asam and in Burma, those from the latter province having 

 also been referred to the above named species by Dr. Gtinther ; and another 

 specimen of the same species was noted by Blyth from Mergui. (Jomn. A. 

 S. B., 1855, xxix, p. 716). 



The Sikkim specimens present, however, certain variations which deserve 

 special notice, because they are important as regards comparison with allied 

 forms. The two nasals generally form a distinct suture between rostral and 

 anterior frontal, rarely do these four shields meet in one point. In one spe- 

 cimen the anterior frontal is regularly divided into two shields. The nasal 

 is followed at the hinder inferior edge by a triangular shield, which rests on 

 the posterior upper half of the first upper labial. In two specimens the 

 anterior corner, and in one the upper corner is detached from the inferior 

 postnasal and forms a separate little shield by itself. One specimen has on 

 one side 3, on the other 4 chin-shields, and four specimens have regularly 4< 

 pairs of chin-shields, the two first pahs representing in size exactly, or very 

 nearly, the first pair of such specimens as have only 3 pahs of chin-shields. 



There are always 8 longitudinal rows of enlarged scales on the upper 

 side of the neck, separated from the occipitals by only a few smaller scales. 

 Of those 8 rows the outermost on each side has the smallest scales and, al- 

 though it can generally be traced at the side of the body, it always remains 

 indistinct, somewhat irregular and is occasionally broken up, and the scales 

 never enlarge in size. The other six rows are well marked on the neck and 

 have most probably given rise to the specific name sexlineatus. The outer 

 row on each side becomes somewhat obsolete before it reaches the shoidder, 

 while the remaining four rows of enlarged scales continue on the body, and 

 down to the tip of the tail. To these four rows Daudin's name quadrilinea- 

 tus evidently applies. 



* The reference ' I. B,.' stands for Dr. Giinther's ' Eeptiles of British India.' 



