54. ZAMENIS. 411 



oontacb with the frontal ; two postoculars, with a subocular below ; 

 three anterior temporals ; ten upper labials, fourth and fifth 

 entering the eye. Scales perfectly smooth, in 31 rows. Ventrals 

 distinctly angulate laterally, 245-254 ; anal divided; subcaudals 84. 

 Above greyish or reddish, with a dorsal series of X-shaped dark 

 spots, and, on each side, a series of light round spots ; flanks with 

 small brown spots ; head with symmetrical dark markings. 



Total length 735 millim. ; tail about one fifth of the total. 



Bakel, Upper Senegal. 



29. Zamenis diaieiua. 



Russell, Ind. Serp. ii. pi. xxx. (1801) ; Geoffr. Descr. Eqypte, Rept. 



pi. viii. fig. 1 (1809). 

 Coluber versicolor (Opp.), Wagl. Syst. Ampfi. p. 189 (1830). 



diadeuia, Schleg. Rhys. Serp. ii. p. 148 (1837). 



cliffordii, Sdhleg. I. c. p. 163, pi. vi. fin's. 13 & 14. 



Periops parallelus, Dum. ^ Bibr. vii. p. 678 (1854) ; Jan, loon. Gen. 



20, pi. ii. (1867;. 

 Zamenis clittbrdii, Giinth. Cat. p. 104 (1858) ; Strauch, Erp. Alg. 



p. 61 (1862), and Schlang. Russ. R. p. 105 (1873) ; Rlanf. Proc. 



Zool. Soc. 1881, p. 679. 

 diadema, Giinth. Rept. Brit. Ind. p. 252, pi. xxi. fig. G (1804) ; 



Anders. Proc. Zool. Soc. 1871, p. 174 ; Stoliczka, Pruc. As. Soc. 



Bmvg. 1872, p. 82 ; Blanf. Zool. E. Pers. p. 412 (1876), and Jour?/. 



As. Soc. Beng. xlviii. 1879, p. 125 ; Murray, Zool. Sind, p. 377 



(1884) ; Fischer, Jahresb. Hami. Wiss. Anst. ii. 1885, p. 102 ; 



Boettg. Zool. Jahrb. iii. 1888, p. 925 ; Bouleng. Faun. Ind., Rept. 



p. 328 (1890), and Tr. Zool. Soc. xiii. 1891, p. 148. _ 

 Periops parallelus, var. achirazana, Jan, in i)e Filippi, Viagg. Pers. 



p. 356 (1865). 

 Zamenis (Periops) versicolor, Boettg. in Kobdt, Reisen Alg. Tunis, 



p. 458 (1885). 



Eostral as deep as broad or a little broader than deep, visible 

 from above ; praefrontals usually broken up into several shields, 

 there being frequently three transverse series of shields between the 

 rostral and the frontal ; frontal ouce and one fourth to once and a 

 half as long as broad, as long as or slightly shorter than its distance 

 from the end of the snout, and usually shorter than the parietala ; 

 loreals three to five; two to four (rarely one) praeoculars, the 

 upper usually in contact with the frontal ; three or four postoculars ; 

 a series of suboculars separate the labials from the eye ; temporals 

 small and numerous, scale-like ; ten to thirteen upper labials ; five 

 lower labials in contact with the anterior chin-shields, which are 

 nearly as long as the posterior. Scales usually more or less obtusely 

 keeled, in 25 to 33 rows. Yentrals usually obtusely angulate 

 laterally, 210-278 ; anal entire ; subcaudals 65-110. Pale buff or 

 sandy grey above, with more or less marked dark spots, of which the 

 median usually form a series of rhombs ; lower parts white, rarely 

 with small blackish spots. A variety (atriceps, Fischer) occurs in 

 Northern India, which is remarkable for having the head entirely 



