124 REPORT OF NATIONAL MUSEUM, 1914. 



ceratops^ of specimens of the trachodont reptile Hypa/^roscmvun^ and 

 of the turtle Echmatemys; and the remounting of the hind limbs of 

 Allosaurus fragilis. The principal mammalian material prepared 

 was the fine porpoise skeleton from Chesapeake Beach, Md., and a 

 considerable part of the collection from the Pleistocene cave deposit 

 near Cumberland, Md. Complete or partial skeletons of Brachycera- 

 tops nwntane7isw, /Stegosaurus, Trachodon, Sinopa, Euplatygonus, 

 Epigaulus, and Canis dims were ready for mounting at the close of 

 the year. 



]Vlr. James W. Gidley, assistant curator in charge of fossil mam- 

 mals, extended his study of fossil pycnodont fishes to include three 

 additional forms, descriptions of which were published during the 

 year. He also continued work on the Fort Union material and sub- 

 mitted a paper defining an important species apparently represent- 

 ing some of the living families of Australian marsupials. A second 

 paper on two other groups of Fort Union mammals was practically 

 completed. In addition to descriptions of several new species, it 

 includes a general discussion in which a genus of the creodont family 

 Arctocyonidse is advocated as representing the ancestral group which 

 gave rise to the modern bears. Further investigation of this basal 

 Eocene material emphasizes more and more its great importance. 

 Already recognizable representatives of at least five modern groups 

 of mammals, not heretofore believed to have existed at so early a 

 stage, have been found, and the final result will doubtless be to very 

 materially change the accepted theories regarding the derivation and 

 phyletic relations of the later prehistoric and present-day groups of 

 mammals. 



Mr. Charles W. Gilmore, assistant curator in charge of fossil 

 reptiles, completed an extended paper on the "Armored dinosaurs 

 in the United States National Museum, with especial reference to the 

 osteology of Stegosaurus," which had been in preparation for three 

 years. He also published a description of the new genus and species 

 Brachyceratops montaiiensis^ a small horned dinosaur from the 

 Upper Cretaceous of Montana, and made good progress on a more 

 detailed account of the osteology of the same and of other reptiles 

 from Montana, which will be issued by the Geological Survey under 

 whose auspices the material was collected. The osteology of Thes- 

 celosaurus, a preliminary account of which was printed the previous 

 year, was likewise the subject of study by Mr. Gilmore, and he had 

 in preparation a chapter on the Dinosauria and other fossil reptiles 

 for a geological giiidebook to be published by the Survey. 



The services of Dr. C. R. Eastman were secured to revise the col- 

 lection of fossil fishes, on which he was engaged during the last half 

 of the year. Over 5,000 individual specimens, besides a large number 

 of fragments, were examined; old identifications were verified or 



