Opisthoctenodon. 73 



specimens have been found, no tuskless forms have yet been 

 discovered. Another argument against the view is that in the 

 Upper Karroo beds, though Diri/iiodoit is common, OudrnodDH. has 

 not yet been discovered, so far as I am aware. 



A description of the bones of the ])ostcraniaI skeleton will be 

 published elsewhere in connection with a large series of other 

 Endothiodont remains. Here it may be well to state that the 

 clavicle is long and very mammal-like, the inter-clavicle a small 

 flat oval bone, and the sternum an irregular flat rounded bone 

 about twice the size of the interclavicle. The humerus, radius 

 and ulna are of the regular Anomodont type, but much more 

 feebly developed than in Oudenodon. The carpus agrees fairly 

 well with that of Oudenodon, but appears to have a prepoUex. 

 The phalanges are long and slender and the fil'tli digit appears to 

 be absent. 



Fig 1, plate IV, shows upper view of the skull. 



On a new Species of Oudeindon (O. t)-igonicepfi). — liy \\. 

 Broom, M.D., B. 8c„ C.M.Z.S., Victoria College, Stellenlx.seh. 



In 1901 I communicated to the Zoological Society of London 

 a paper on the structure and affinities of Oudenodon, in which was 

 described the almost perfect skeleton of a small form. Owing to 

 the extremely weathered condition of the up})ei- surface of the 

 skull, it was impossible to decide with certainty to what species it 

 belonged, and I referred it doubtfully to (>. gi-acilis. The only 

 part of the skull in the small skeleton sufficiently well preserxcd 

 to be of service in determining the species, is the lower jaw, and 

 as unfortunately the lower jaw of 0. grdciIiH is unknown, it has 

 been impossible till recently to definitely settle the question. 

 Within the last year, however, I have discovei-ed two well-preser- 

 ved small Oudenodon skulls, both with the lower-jaws in position: 

 and while there is no doubt that both the new skulls belong to 

 the same species as the small skeleton, they are both quite distinct 

 from Oudenodoii gracilis. As the new form also difliers from the 

 other previously described species, I propose to call it Oiidcnodon 

 trigonicejjs. The better preserved of the two skulls wdiich I 



