138 ME. G. A. BOULENGER ON THE 'EEPTILES 



by two fringed scales. Rostral very large, forming a suture with tlie frontonasal or in 

 contact with the anterior angle of the latter shield ; six supraoculars; parietals shorter 

 than the interparietal, followed by three to five pairs of nuchals ; seven to nine upper 

 labials. 26 to 28 (very rarely 30) scales round the middle of the body, all perfectly 

 smooth ; dorsals usually not or scarcely larger than ventrals. Sides of belly angular. 

 Digits much depressed and strongly serrated laterally. Yellowish or brownish above, 

 each scale with small brown and whitish spots or shafts ; frequently with more or less 

 marked dark transverse bands across the body; lower parts uniform whitish. 



From snout to vent 120 millim., tail 85. 



This species inhabits the Sahara and the borders of the Red Sea. It is not recorded 

 from Morocco, but was found by M. Maury at Ain-Sefra, in the south of the Province 

 of Oran, close to the Moroccan frontier. M. Lataste found it common in the Algerian 

 and Tunisian Sahara ; its occurrence further north, at Djelfa, for instance, whence it is 

 recorded by Strauch on the authority of Loche, is doubtful. It is only found in the 

 sand, in which it burrows with great rapidity. It is eaten by the Arabs. 



Very good figure in 'Description de I'Egypte,' Rept., Suppl. pi. ii. fig. 8. 



4. Chalcides, Laurenti, 1768. 



Palatine bones not meeting on the median line of the palate, which is toothless. 

 Eyelids movable, lower with an undivided transparent disk. Nostril pierced between 

 the rostral and a very small nasal, in an emargination of the former shield ; supranasals 

 present; prsefrontals and frontoparietals absent. Limbs short or rudimentary. 



Six species in Barbary, distinguishable as follows : — 



A. Snout conical. 



a. Ear-opening much larger than the nostril. 



Limbs pentadactyle 1- ocdlatus. 



Limbs tridactyle; second and third toes equal 2. lineatus. 



Limbs tridactyle ; second toe longer than third 3. tridacttjlns. 



b. Ear-opening not or scarcely larger than the nostril. 



Limbs tetradactyle (rarely pentadactyle) 4. mlonedon. 



Fore limb didactyle, hind limb tridactyle 5. mauritanicus. 



B. Snout wedge-shaped; sides of belly angular ; limbs penta- or tetradactyle . 6. sepoides. 



1. Chalcides ocellatus, Forskal, 1775. 



Snout obtuse, scarcely projecting beyond the labial margin ; ear-opening much larger 

 than the nostril. Nostril pierced just above the suture between the rostral and the 

 first labial ; supranasals distinct ; frontal longer than broad ; usually the fifth labial 

 entering the orbit. Body cylindrical or rather depressed. 24 to 40 scales round the 

 middle of the body. Limba short but well developed and pentadactyle ; length of the 

 bind limb thrice and one third to four and a half times in the length from snout to 



