190 



THE CEEATOPSIA. 



the skeleton bears its catalogue number, and all plaster bones are marked with a red +. There is thus preserved a definite 



record of all the associated material comprising the composite skeleton. * * * 



The skeleton as mounted is standing on a base of artificial matrix intended to represent the color and texture of the 



Laramie sandstone in which the remains of these animals are found. 



From the tip of the beak to the end of the tail the skeleton as restored is 19 feet 8 inches in length. The skull, which 



is 6 feet long, equals nearly one-third of this length [a re- 

 markable proportion]. At the highest point (the top of the 

 sacrum) the back is 8 feet 2 inches above the base. The 

 mounted skeleton presents several features which would other- 

 wise be lost to the observer if seen in the disarticulated condi- 

 tion. The short body cavity, the deep thorax, the massive 

 limbs, and the turtle-like flexure of the anterior extremities are 

 characters appreciated only in the mounted skeleton. The 

 position of the. forelimbs in the present mount appears rather 

 remarkable for an animal of such robust proportions, but a 

 studjr of the articulating surfaces of the several parts precludes 

 an upright mammalian type of limb, [such] as was represented 

 by Marsh in the original restoration. * * * The [tail and] 

 forefeet are perhaps the most conjectural parts of the whole 

 restoration. [The tail is restored almost wholly from Marsh's 

 drawing of this animal.] Mr. Hatcher, after a careful study of 

 all the forefoot material [of this group] known, was unable to 

 arrive at a satisfactory conclusion as to the arrangement or the 

 number of bones comprising the manus. In constructing these 

 parts we have largely followed Marsh's drawing, assisted some- 

 what by forefoot material kindly loaned by Dr. H. F. Osborn, 

 of the American Museum of Natural History, New York City. 

 [It seems probable that a similar condition prevailed in this 

 animal to that found in the other better known dinosaurs, so 

 instead of introducing a full complement of carpal and tarsal 

 bones, as was done in the first restoration, only two elements 

 were modeled to represent the carpus, while the astragalus 

 alone, comprises the. tarsus.] 



The nasal horn [core] of the skull used in the present skele- 

 ton appears to be missing, and on account of the unsatisfactory 

 evidence as to whether the horn is wholly or only partly gone, 

 it was decided not to attempt a restoration at this time. This 

 will account for the absence [or rather the apparent lack of 

 development] of one of the important features upon which the 

 name of the. animal is based, Triceratops meaning three-horn 

 face, in allusion to the presence of the two large horns above the 

 eyes and a third, smaller horn on the nose. 



It may be of interest to mention here that Professor Marsh 

 used this skeleton (No. 4842), supplemented by other remains 

 now preserved in the collections of the Yale University Mu- 

 seum, for the. basis of his restoration of Triceratops prorsus, 

 published as PI. LXXI in the Dinosaurs of North America 

 [fig. 125]« Pis. LXIV-LXVIII in the same work were also 

 largely reproductions of parts of this same individual 



A comparison of the above-mentioned restoration by 

 Marsh [fig. 125] with the mounted skeleton [PL XLLX of this 

 work] shows several differences in points of structure, due 

 chiefly to the better understanding of these extinct forms. 

 The most striking dissimilarity is in the shortening of the trunk 

 by a reduction of the number of presacral vertebra?. Marsh's 

 error was due to an overestimate of the, length of this region, 

 a mistake also made in his restoration of Brontosaurus 

 (=Apatosaurus) , as has been shown by Riggs.b Mr. Hatcher 

 determined from a well-preserved vertebral column in the Yale 



University Museum the number of presacrals as twenty-one, c this being six less than was ascribed to the animal by Professor 



Marsh. 



a Sixteenth Ann. Rept. U. S. Geol. Survey, pt. 1, p. 386. 



b Science, new ser., vol. 17, March 6, 1903, pp. 393-394. 



c Doctor Lull now recognizes twenty-two presacrals (see p. 47). 



