Three new Snakes from South Arabia. 179 



suture with the frontal, with a subocular below it ; two 

 postoculars ; temporals 2 + 2 or 2 + 3; eight upper labials, 

 fourth and fifth entering the eye ; four or five lower labials 

 in contact with the anterior chin-shields ; posterior chin- 

 shields as long as the anterior and separated from each other 

 by two series of scales. Scales smooth, in 17 rows. Ventrals 

 155-169; anal divided ; subcaudals 80-90. 



Total length 380 mm. ; tail 110. 



The specimens at hand, ten in number, exhibit a surprising 

 amount of colour- variation. Tliey may be arranged under 

 seven heads : — • 



A. Olive-grey above, -with a dorsal series of large, brown, dark-edged, 



transverse spots and a lateral series of similar spots alternating with 

 them ; two dark bars on the head, the first across the eyes, the 

 second across the temples and the parietal shields ; a third bar 

 across the nape ; lower parts white. 



a. 6 • V. 157. C. 83. El Kubar. 



6. J . V. 162. C. 84. Schaf Ravine. 



B. Similar to the preceding in the markings, but reddish brown, with a 



bright red vertebral stripe ; ventral shields spotted with red on the 

 sides. 



c. 6. V. 157. C? Schaf Ravine. 



C. Body orange, with a bright red vertebral stripe, the scales and shields 



edged with brown ; no spots ; head olive-grey above, the temples 

 and nape black. 



d. $. V. 161. C. ? El Kubar. 



D. Scales brown or black, with yellowish or pale olive centres ; ventral 



and subcaudal shields whitish, edged with brown or blackish ; head 

 olive-grey in front, black behind. 

 e-i. 6 (V. 159, 157 ; C. 83, 83) & $ (V. 165, 1G9, 165 ; C. 80, 89, 82). 

 El Kubar. 



E. Olive-grey above, the scales edged with blackish ; whitish or grey 



beneath, the shields edged with dark grey or blackish. 

 k-l. 6- V. 155, 161. C. ?, 90. El Kubar. 



F. Black, scales and shields speckled with white ; head and nape olive- 



grey. 

 m. $. V. 161. C. ? El Kubar. 



G. Black above, dark grey below ; throat and anterior ventral shields 



white. 

 n. $ . V. 168. C. 82. El Kubar. 



In the low number of its ventral shields Z. variabilis agrees 

 with Z. brevis, Blgr., from Somaliland, which differs in the 

 less prominent snout, the smaller rostral shield, the narrower 

 frontal, the upper labials nine in number, and the scales in 

 19 rows. 



