132 Lacertidie. 



but also in the shape aud arrangement of the head-shields, especially 

 those surrounding the nostril, and the occasional separation of the 

 fourth supraocular from the frontoparietal.* and of the ventral shields. 

 As the scaling of the back and the coloration may well be derived from 

 the condition in L. vivi])ara, I have little doubt that the genus Tachy- 

 dromus is to be regarded as directly descended from an oriental species 

 of Lacerta connected with L. vivi])ara. 



2. TACHYDEOMUS TACHYDROMOIDES. 



Lacerta tacJiydromoides, Schleg. Faun. Japon., Kept. p. lUl, pi. i, 

 figs. 5-7 (1838). 



Taclnjdronivs jajwnicnSj'Dnm. & Bibr. Erp. Gcu. v, p. 161 (1839) ; 

 Giinth. Eept. Brit. lud. p. 69 (1864) ; Hilgend. Sitzb. G-es. Nat. Fr. 

 Berl. 1880, p. 112. 



Tachysanrusja2)onicus,Grra.y, Cat. Liz. p. 52 (1845). 



Tacliydromus tachydrom aides, part., Bouleng. Cat. Liz. iii, p. 5 

 (1887).' 



TacJiydromus tachydromoides, Giinth. Ann. & Mag. JST. H. (6) i, 1888, 

 p, 169 ; Stejueger, Herp. Japan, p. 247, fig. (1907) ; Bouleng. Mem. 

 As. Soc. Beng.V, 1917, p. 212. 



TacJiydromus holsti, Bouleng. Proc. Zool. Soc. 1894, p. 733, pi. xlix, 

 fig.l. 



Body feebly depressed. Head 1^ to If times as long as broad, its 

 depth equal to the distance between the anterior corner of the eye aud 

 the tympanum, its length 3| to 4 times in length to vent in males. 4 

 to 4| times in females ; snout pointed, with strong canthus and nearly 

 vertical loreal region, as long as the postocular part of the head. 

 Pileus 1| to 2 times as long as broad. Neck as broad as the head. 

 The hind Ynwh reaches the axil, the shoulder, or the collar in males, the 

 wrist, the elbow, or the axil in females ; foot 1 to li times as long as 

 the head. Tail 2 to 3^, times the length of head and l)ody (If times 

 in the veiT young). 



Nostril pierced between three shields. Eostral not entering the 

 nostril, nearly always in contact with the frontonasal,! usually broadly ; 

 frontonasal as long as broad or slightly l)roader, as bi'oad as the 

 internarial space or a little broader ; prefrontals forming a median 



* A character which has become fixed in T. sexlineatus, at the other end of 

 the series. 



t Two excei)tions, male from Koshiku and female from Koyosun, in which 

 the nasals meet behind the rostral. 



