CONTENTS. VII 



Chapter IV. Systematic descriptions of genera and species — Continued. Page. 

 Revision of species of Judith River Ceratopsia — Continued. 



Genera and species described by Professor Cope — Continued. 

 Monoclonius — Continued . 

 M. crassus — Continued. 



Description of type specimen 72 



Principal measurements 80 



M. fissus 81 



M. recurvicornis 81 



M. sphenocerus 87 



Genera and species from the Judith River beds of Canada, described by Lambe. 88 



Monoclonius dawsoni 89 



M. canadensis 93 



M. belli 96 



Stegoceras 97 



S. validus 98 



Genera and species described by Professor Marsh 100 



Ceratops 100 



C. montanus 100 



C. paucidens 103 



Species erroneously referred to Ceratops 104 



Review of the species of Laramie Ceratopsia 104 



Genera and species described by Professor Cope 104 



Agathaumas ■ 104 



A. sylvestris 105 



Locality 105 



Description by Cope 106 



Material now available 108 



Detailed description 109 



Principal measurements Ill 



A. milo Ill 



Polyonax , '. Ill 



P. mortuarius 112 



Manospondylus Cope _ 113 



Manospondylus gigas 113 



Claorhynchus 114 



C. trihedrus 114 



Genera and species described by Marsh and Hatcher, chiefly from Converse County, Wyo 115 



Ceratops Marsh 115 



Ceratops alticornis 115 



Triceratops 116 



T. (Ceratops) horridus 117 



Discovery 117 



Original description 118 



Ceratops horridus made the type of the new genus Triceratops 118 



Description of type 119 



T. serratus 122 



Locality and horizon 122 



Original description 122 



Further description 123 



Principal measurements 126 



T. prorsus 127 



Original description 127 



Locality : 127 



Detailed description of type specimen 128 



Principal measurements 131 



T. galeus 132 



T. sulcatus 133 



T. elatus 134 



Locality 135 



Original description 135 



Specific features 135 



Principal measurements of type 136 



Description of plesiotype 136 



Measurements of plesiotype 138 



