Scaptira. 349 



suggested dipliyletic origin of the genus Equus. But whereas in tlie 

 case of the horses the terminus foi-ni would result from two long chains 

 of parallel genera, here on the contrary the convergent branch-ends 

 are independently issued from forms so closely related that one would 

 not feel justified in breaking them up into genera. 



Synopsis of the Species. 



Section I. Meroles, Gray. Ventral plates in straight longitudinal series ; 

 snout conical ; ear-opening entirely exposed, with projecting scales on the 

 anterior border ; toes compressed, keeled inferiorly. — S. Africa. 

 Scales teeled, 42 to 62 across middle of body ; ventral plates 

 in 12 (rarely 10) longitudinal series; nasals in contact 

 behind the rostral ; lower nasal largely in contact with the 

 rostral; prefrontals rarely meeting on the median line; 

 interparietal usually in contact with a small occipital ; toes 

 feebly serrated laterally ; 13 to 20 femoral pores on each 

 side ... .8. knoxii, M.-Edw., p. 350. 



Scales smooth or feebly keeled, GO to 75 across middle of body ; 

 ventral plates in 12 or 14 (rarely 16) longitudinal series ; 

 frontonasal in contact with the rostral ; lower nasal largely 

 in contact with the rostral ; prefrontals usually forming a 

 median suture ; parietals meeting on the median line ; 

 occipital minute or absent ; toes feebly serrated laterally ; 

 14 to 21 femoral pores . . . S. suborbitalis, Peters, p. 354. 



Scales keeled on posterior part of back; ventral plates in IS 

 longitudinal series ; nasals in contact behind the rostral ; 

 lower nasal not reaching the rostral ; prefrontals forming a 

 median suture ; no occipital ; toes strongly serrated 

 laterally ; 20 to 23 femoral pores S. reticulata. Socage, p. 357. 



Section II. Saurites, Peters. Ventral plates tessellated or forming oblique 

 longitudinal series ; snout much flattened, with angular labial margin ; ear- 

 opening partly covered by si. dermal fold ; lower nasal largely in contact with 

 the rostral ; toes compressed, keeled inferiorly, strongly serrated on the outer 

 edge. — S. Africa. 



Scales smooth or obtusely keeled, 78 to 92 across middle of 

 body ; a lateral band of enlarged keeled scales on the 

 posterior part of the back; 22 to 26 ventral plates in the 

 longest transverse series; nasals nearly meeting or forming 

 a suture behind the rostral ; 27 to 37 femoral pores on each 

 side . . . . S. ctenodactijla, A. Smith, p. 358. 



Scales all smooth, 90 to 110 across middle of body ; 26 to 30 

 ventral plates in the longest transverse series ; frontonasal 

 forming a suture with the rostral ; 16 to 24 feiioral pores. 



S. cimeirostris, Strauch, p. 361. 



Section III. Scaptira, =. str. Ventral plates tessellated or forming oblique 



longitudinal series ; snout conical; ear-opening entirely exposed ; lower nasal 



not or but narrowly in contact with the rostral ; toes compressed or depressed, 



moderately or strongly serrated laterally. — S.W. and C, Asia. 



