326 O. C. Marsh — Notice of New Fossil Mammals. 



tapering rapidly in front. There is a well-marked sagittal 

 crest, and a strong constriction between the temporal openings. 

 The frontal bones expand rapidly forward, and meet the broad, 

 smooth nasals, which converge anteriorly into the pointed ends 

 which have suggested the specific name. The paroccipital 

 process is strong and elongate, and the post-glenoid is shorter 

 and more massive. The premaxillary bones are weak, and pro- 

 ject considerably beyond the end of the nasals. They each 

 supported a single incisor. 



A striking feature of the skull is the very large size of the 

 molar teeth, which are well shown in figure 4. 



There were no lower jaws found with the present skull, but 

 in other specimens of this species, they are well represented. 

 Each ramus is of moderate depth, the angle rounded, and the 

 lower border gently convex below. On each side of the sym- 

 physis is a small incisor, and outside of this, a large, worn 

 tooth, which is probably a canine. There is a short diastema, 

 and behind this, are six robust teeth. 



The locality of these remains is in Phillips County, Kansas, 

 and the special horizon in which they occur so abundantly is 

 in the Pliohippus beds of the Upper Pliocene. The specimens 

 here described were obtained by J. B. Hatcher of the U. S. 

 Geological Survey. 



Brontotherhle. 



The large collections of the Brontotheridce secured by the 

 writer in his various expeditions in the West have been supple- 

 mented by important discoveries made during the last two 

 years, mainly under the auspices of the U. S. Geological Sur- 

 vey. Remains of more than one hundred individuals, many 

 of them with the skulls in good preservation, have recently 

 arrived in New Haven, and are now under examination. The 

 results of an investigation of the whole group will be brought 

 together by the writer, in a monograph now well advanced 

 toward completion. Some of the more important of the new 

 forms are briefly described below, and these will all be fully 

 illustrated in the monograph. 



Brontops robustus, gen. et sp. nov. 



The present genus is quite distinct from any of the forms 

 previously described, and the type is the most perfect specimen 

 of this group yet discovered. The skull and lower jaws are 

 almost as perfect as in life, and the greater part of the skeleton 

 has also been secured. The skull is large and massive, with 

 widely expanded zygomatic arches, and short and robust horn- 

 cores, projecting well forward. In general form, it resembles 



