REPTILES FROM SOUTH AFRICA. 1077 



Suborder T h E R o c; e p h A l i A. 



yELUROSAURUS WHAITSI, Sp. 11. (PI. LXIII. fig. 8.) 



This new species of ^lurosaurus was obtained by Mr. Whaits 

 at Beaufort West. uElurosaurus felinus also occurs at Beaufoi't 

 West on the same horizon, but the difiierence between the species 

 is considerable apart from size. 



The specimen consists of the greater part of the left dentary, 

 much of each maxilla, the left premaxilla, and numerous other 

 fragments of the skull, besides a large number of fragments of 

 the postcranial skeleton. The skeleton is so imperfect that no long 

 bone is entire, and most are represented by articular ends. 

 A few imperfect vertebrte are present, and a number of dis- 

 articulated bones of the manus and pes. 



The symphysial part of the jaw makes a less obtuse angle Avith 

 the lower border of the ramus than in u.Elurosaur us felinus. 



There are four lower incisors and a single large canine. In the 

 type only the deep part of the root of the first incisor is left, so 

 that an accurate measurement of the space occupied by these teeth 

 is impossible. The last is situated very close to the canine. All 

 the incisors are subequal and rounded. The canine measures 

 10 mm. X 6'5 mm. at the base; the height is not shown. The 

 molars are small and degenerate. The exact number is uncertain ; 

 three remain in the jaw, but a^iparently two have been shed and 

 replaced by bony tissue. Probably the j'oung animal had 5 molars 

 (possibly 6). There is a large diastema of 15 mm. between the 

 canine and what is probably the occupied position of the 1st 

 molar, and the five molars have a space of 13 mm. From the front 

 of the jaw to the back of the last molar is a distance of 48 mm. 



The upper incisors are badly preserved, but the roots are 

 preserved and occupy a space of 21 mm. The upper canine is 

 large and but slightly curved ; its anterior border is smooth and 

 rounded ; the posterior border is serrated. The antero-posterior 

 measurement at the base is 1 1 mm. 



It seems not improbable that specimen R 855 a in the British 

 Museum may belong to this species. 



^LUROSAURUS TENUIROSTRIS, sp. n. (PI. LXIII. fig. 9.) 



This species is founded on a snout collected by myself at 

 Kuilspoort. It resembles uElurosaurus lohaitsi very closely, but 

 differs in that, though it is probably a rather larger form, the 

 snout is more slender and the mandible feebler. 



The five upper incisors measure 24 mm. as compared with 21 mm. 

 in ^^. tchaitsi, and the whole measurement from i^ to 9ft' is 65 mm. 

 in ^^. tenuirostris as compared with about 52 mm. in ^. zohaitsl. 



Some of the lower incisors are well preserved. The first is a 

 i-ounded pointed tooth with a feeble serrated ridge on its outer 

 a,nd posterior side. On the third incisor there is only a very 

 slightly marked ridge, and there are no distinct serrations, though 

 it is possible that they have been worn off by friction against 



Proc. ZooL. Soa— 1911, No. LXXIII. 73 



