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7. On Two New S-pecies of Dicynodon. By E. BBOOM, M.D., D.Sc., 



and S. H. HAUGHTON, B.A. 



DICYNODON TESTUDIEOSTRIS, sp. nov. 



THE type of this new species (No. 2354 S.A.M.) was collected at 

 Dunedin, Beaufort West, just south of the Homestead, and is prob- 

 ably from the Cistecephalus zone. It is a small skull of a female, 

 measuring in greatest length 85 mm., or, allowing for slight crushing, 

 probably originally 90 mm. The greatest breadth is 56 mm. From 

 the snout to. the front of the orbit is only about 18 mm. when the 

 skull is viewed directly from above. The orbit is about 20 mm. in 

 length, and from the front of the postorbital arch to the back of the 

 squamosal is about 47 mm. 



Two specimens were discovered near the same spot, which agree 

 closely. Both are tuskless, and would formerly have been placed in 

 the genus Oudenodon, but we now know that this is the female of 

 Dicynodon. In a number of respects the present species differs 

 remarkably from the Dicynodons of a lower horizon, and it will 

 probably be necessary to break up the genus later on. At present, 

 however, we do not know enough safely to do so, and for a time we 

 may conveniently place all in the old genus Dicynodon, even though 

 the number of species is becoming large. 



The beak is very short, and the caniniforni process lies under the 

 middle of the orbit. The arrangement of bones round the nostril is 

 remarkable. The premaxilla is, as always in Dicynodon, unpaired. 

 It is flattened in front and rounded at the sides. It passes up 

 between the nostrils and between the nasals. The maxilla, though 

 not large, forms practically the whole of the cheek. It almost 

 reaches to the orbit, hiding the jugal and lachrymal except just at 

 the orbital margin. It forms the anterior margin of the nostril and 

 has a fairly long articulation with the nasal. 



There is no evidence of a septomaxillary, at least on the outer side 

 of the skull. Whether there may be one hidden underneath it is, 

 impossible to say without damaging the skulls. We incline, how- 

 ever, to think that the septomaxillary is absent. Formerly it was 



