340 O. O Marsh — Restoration of Triceratops. 



massive fore limbs, proportionally the largest in any known 

 Dinosaur, correspond to the head, and indicate slow locomotion 

 on all four feet. 



The skull is, of course, without its strong horny covering on 

 the beak, horn-cores, and posterior crest, and hence appears 

 much smaller than in life. The neck seems short, but the first 

 six cervical vertebrae are entirely concealed by the crest of the 

 skull, which in its complete armature would extend over one 

 or two vertebrae more. The posterior dorsals with their double 

 headed ribs continue back to the sacrum itself, there being no 

 true lumbars, although two vertebrae, apparently once lumbars, 

 are now sacrals, as their transverse processes meet the ilia, and 

 their centra are coossified with the true sacrum. The four 

 original sacral vertebrae have their neural spines fused into a 

 single plate, while the posterior sacrals, once caudals, have 

 separate spines directed backward. 



No attempt is made, in this restoration, to represent the 

 dermal armor of the body, although in life the latter was more 

 or less protected. Various spines, bosses, and plates, indicating 

 such dermal armature, have been found with remains of this 

 group, but the exact position of these specimens can, at present, 

 be only a matter of conjecture. 



This restoration gives a correct idea of the general propor- 

 tions of the entire skeleton in the genus Triceratops. The 

 size, in life, would be about twenty-five feet in length, and ten 

 feet in height. The genus Oeratops so far as at present known 

 is represented by individuals of smaller size, and in some 

 instances, at least, of quite different proportions. A third 

 genus, which may be called /Sterrholophus, can be readily dis- 

 tinguished from the other two by the parietal crest, which had 

 its entire posterior surface covered with the ligaments and 

 muscles supporting the head. In Oeratops and Triceratops, a 

 wide margin of this surface was free, and protected by a thick, 

 horny covering. The type of the new genus is the specimen 

 described and figured by the writer, as Triceratops flabellatus, 

 which in future may be known as Sterrholophus flaoeUatus, 

 Marsh. There is some evidence that other forms, quite dis- 

 tinct, left their remains in essentially the same horizon of the 

 Laramie, but their true relation to the above genera cannot be 

 settled without further discoveries. 



This group so far as at present investigated is very distinct 

 from all other known Dinosaurs, and whether it should be 

 regarded as a family, Oeratopsidw, as first described by the 

 writer, or as a sub-order, Oeratopsia, as later defined by him, 

 will depend upon the interpretation and value of the peculiar 

 characters manifested in its typical forms. 



