290 COLUBRID, 
Tropidonotus natrix, var. concolor, F. Miill. 1. ¢. 
natrix, var. astreptophorus, Seoane, Idend. de Lacerta schreiberi, 
§e., p. 15 (1885). 
Eye moderate. Rostral broader than deep, visible from above ; 
internasals at least as broad as long, trapezoid, shorter than the 
prefrontals ; frontal once and one third to once and a half as long 
as broad, as long as its distance from the end of the snout or a little 
shorter, shorter than the parictals; loreal deeper than long; one 
(rarely two) pre- and three (rarely two or four) postoculars ; tem- 
porals 1+2; seven upper labials, third and fourth entering the eye ; 
four or five lower labials in contact with the anterior chin-shields, 
which are shorter than the posterior. Scules strongly keeled, of 
outer row smooth or faintly keeled, in 19 rows. Ventrals 157-190; 
anal divided ; subcaudals 50-8. Grey, olive, or brown above, with 
black spots or narrow cross-bands ; labials white or yellowish, with 
the sutures between the shields black ; belly usually checkered black 
and white or grey. 
Total length 1120 millim.; tail 210. Reaches a length of two 
metres (63 feet). 
Europe, Algeria, West and Central Asia. 
A. The typical form. A white, yellow, or orange collar, usually 
divided in the middle, sometimes absent, bordered behind by a 
broad deep black collar, which is constant. 
a. 2 (V. 166; C. 58). Hale, near. Salis- Rev. H. G. W. Aubrey 
bury, [P.}. 
b, e, d-e. 2 (V. 161,165; Devonshire. 
C. 55, 58), hgr. ¢ (V. 
173; C. 64), & yg. (V. 
166; C, 66). 
tg, h. Eggs. London. 
7. ¢ (V. 170; C. 66). England. 
k. 3 (V. 166; C. 60). Gotland. Dr. Eisen [P.}. 
l. 2 (V. 172; C. 58). Sweden. C. J. A. Thuden, Esq. 
P,}. 
m-n. 9 (V. 165, 168; C. Near St. Malo. Pie Boulenger, Esq. 
63, 60). [P.}.- 
9-8. g (V. 175; C€. 71), Bologna. Prof. Bianconi [P.]. 
2 (V. 165, 169; C. 64, 
62), & yg. (V.177, 172; 
C. 76, 72). . 
t-u. Sd (V.176; CO. ?) & Tlisk, E. Turkestan, Rev. H. Lansdell [C.], 
2 (V. 176; ©. 60). | 
v. Yg., two-headed —? 
monster. 
w. Ad., skel. —? 
x,y. Skulls. Paris, 
B. Collar altogether absent, or reduced to a small black blotch on 
each side of the nape. (Var. astreptophorus, Sevane.) 
a. 9 (V. 157; C. 50). Corunna, M. V. L. Seoane [P.]. 
b. ¢ (V. 166; C. 77). Albufera de Va- Lord Lilford [P. 
lencia, s 
