172 



DR. R. BROOM ON 



much crushed obliquely and the occiput is further crushed 

 forwards, so that though the jaws with most of the teeth are in 

 fairly good condition, little of the structure of the upper part of 

 the skull can be satisfactorily made out. 



As the teeth agree in number and structure with those of 

 Scymnognathus whailsi and other known species, and so far as 

 can be seen the skull of this new form does not differ greatly, 

 I refer the new species to this genus and call it S. parvus. 



The total length of the lower jaw is about 170 mm., and the 

 skull probably measured 190 mm. 



The five incisors measure 25 mm. Between i b and the canine 

 is a diastema of 12 mm., and the canine measures 10 mm., 

 followed by a diastema of 10 mm. The four molars measure 

 19 mm. In S. minor, the nearest allied species, the five incisors 

 measure 33 mm., and the four molars 21 mm. 



The specimen is numbered R. 4139 in the British Museum 

 Register. 



Trirachodon browni, sp. n. (Text-fig. 8.) 



This new species is founded on the anterior two-thirds of a 

 small skull discovered by Mr. Alfred Brown at Aliwal North. 

 The skull is well preserved, but owing to the lower jaws being 

 closely fixed to the upper, the crowns of all the molars are hidden. 



Text-figure 8. 



B, 



Trirachodon browni. 



A. Side view of snout. B. Upper view of snout. Nat. size. 

 E.M. R. 3307. 



It is not improbable that when a specimen is discovered which 

 shows the crowns of the molars, this species may have to be placed 

 in a new genus, but as it is certainly a near ally of Trirachodon 

 and possibly belongs to this genus, I have provisionally placed it so. 



