PLATE 46. 



ULNO-RADIUS OF MERYCHIPPUS ISONESUS SECUNDUS, M. ISONESUS TERTIUS, M. ISONESUS QVARTUS, 



M. ISONESUS QUINTUS. 



ANTERIOR AND EXTERNAL VIEWS IN FOUR SPECIES FROM THE SHEEP CREEK BEDS OF NEBRASKA. 



The ulnar and radial shafts in Mcrychippus are partly coossified, the extent of coossification varying in different 

 species and with age. 



All figures one-half natural size. 



Sheep Creek, Nebr. Middle Miocene 1. Meri/chippus isonesus sccundus Osborn, type, Am. Mus. 14179. Anterior 



view. 



" " " " 2. M. isonesus tertius Osborn, type, Am. Mus. 14180. a, Anterior, b, external 



view. 



" " " 3. M. isonesus quartus Osborn, type, Am. Mus. 14184. Anterior view. 



" " " " " 4. M. isonesus quintus Osborn, type, Am. Mus. 14185. a, Anterior, b, 



external view. 



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