Fauna and Stratigraphy of the Stormberg Series. 341 



(molar) teeth are small, single-rooted, and narrow from side to side; 

 the root is deep and closely fits its alveolus." "The crown is of an 

 irregular oval shape, widest in front, where it is about three-quarters 

 of its length. There are four cusps arranged longitudinally and for- 

 ming the outer side of the tooth; .... the first was much the largest, 

 and they gradually decline in size and height to the fourth. On the 

 inner side is a strong cingulum. This shows a very faint crimping". 



Type. Imperfect dentary. 



Locality. Witkop, Albert, C. P. 



Horizon. Red Beds. 



TRITHELEDON RICONOI, Broom. 

 Text fig. 7. 



1912. Broom. Ann. S. Afric. Museum VII, 5, p. 334, PI. XXII, 



figs. 30-36. 



The type of this form is a "portion of a left maxilla with the 

 roots of 7 teeth and two imperfect immature teeth, portion of the 

 left jugal, and a fragment of the left palatine" from Paballong, Mount 

 Fletcher District, Griqualand East, which is in the collection of the 

 South African Museum. 



In 1914, the discoverer of this fragment, the late Dr. M. Ricono, 

 forwarded to the Museum a small parcel containing a portion of a 

 skull and eleven dissociated vertebrae from Paballong, all of which 

 undoubtedly belong to the same animal as the fragment described 

 by Dr. Broom. Dr. du Toit, who has since visited the locality, 

 informs me that the fossil came from the Red Beds. It was found 

 within a quarter of a mile of the spot from which the type of 

 Sphenosnchus acutus came, and from an horizon within 10 or 12 feet of it. 



This new skull fragment consists of the greater part of the right 

 maxilla including the palatal portion, the base of the jugal arch, 

 part of the left maxilla, and a portion of the right palatine. The 

 first seven molars are present. They agree with the description 

 given by Dr. Broom as far as can be seen from the crowns of 

 the 4th and 6th teeth, which are the only teeth preserved entire. 

 The 7 teeth occupy a length of 15'2 mm. 



In front of the 1st. rnolar there is a markedly concave diastema 

 of which a length of 9 mm. is preserved. There is no remnant of 

 the canine present, and if the base of the canine was on the same 

 level as the base of the molars, the diastema would probably have 

 been about 12 mm. long. It has a maximum height of 4 mm. above 

 the base of the teeth. 



