NODOSAURUS TEXTILIS. 155 



rounded in front and more contracted behind, so that in cross section it is ovate, with the apex 

 of the oval directed posteriorly- The anterior surface of the horn core seems to have occupied 

 a plane nearly perpendicular to that of the longitudinal axis of the cranium. The bone is 

 comparatively dense without, but the central mass shows a coarse cancellous structure. 



A broad, low, disarticulated epijugal was found associated with the remains. This differs 

 from the same element in Triceratops in being proportionally much broader and in having a 

 concave inferior surface. The external surface of the bone is marked by deep vascular grooves, 

 and it was united with the jugal by a very irregular suture. 



The general aspect of this skull as seen from above is well shown in fig. 119, from a restora- 

 tion of it by Professor Marsh. An examination of this figure will at once show the striking 

 contrast between the enormously elongated posterior region and the abbreviated facial region, 

 which becomes more especially emphasized when compared with similar views of crania per- 

 taining to the genus Triceratops." 



The detached occipital condyle was found with the type. Considering the size of the parietal 

 crest and the total length of the skull, the occipital condyle was small and the sutures between 

 the different elements composing it were not completely closed; when found it had parted 

 along these sutures and lay in three subequal parts. The lower and median of these was 

 formed by the basioccipital, while the exoccipitals formed the upper two-thirds of the condyle, 

 as shown in fig. 7. The size of the condyle shows that, notwithstanding the enormous size of 

 the frill, the skull proper was not unusually large for a member of the Laramie Ceratopsia, 

 being rather under than over the average size. 



Principal measurements of the type. 



Mm. 



Length of parietals along median line 1 , 432 



Greatest length of parietals 1 , .568 



Greatest length of squamosal .' 1 , 400 



Greatest breadth of squamosal 430 



Estimated length of skull 2, 350 



Greatest distance between external borders of squamosals measured over curved surface 932 



Transverse diameter of supraorbital hom core near base _ 133 



Transverse diameter of supraorbital horn core at middle 82 



Fore-and-aft diameter of supraorbital horn core at middle . Ill 



Fore-and-aft diameter of supraorbital horn core near base , 191 



Fore-and-aft diameter of nasal horn core near base 130 



Transverse diameter of nasal horn core near base. . _ 81 



Circumference of supraorbital horn core near base 510 



Circumference of supraorbital horn core at middle. 125 



Height of epijugal .... _ . 59 



Breadth of epijugal 105 



Diameter of occipital condyle 85 



NODOSAURUS Marsh. 1889. 

 Nodosaurus textilis Marsh. 1889 



Type No. 1815, Yale Museum. 



Original description in Am. Jour. Sci., 3d ser., vol. 38, Aug., 1889, p. 175. 

 Marsh, O. C, Am. Jour. Sci., 3d ser., vol. 39, May, 1890, pp. 424-425; ibid., vol. 50, Dec, 1895, p. 497; Sixteenth Ann. Rept. 



U. S. Geol. Survey, pt. 1, p. 225 (dermal ossicles shown in fig. 5, PI. LXXV). 

 Nicholson and Lydekker, Manual Pal., 1889, p. 1164. 

 Zittel, K. A. von, Handbuch Pal., p. 754. 



The type (No. 1815, Yale Museum) of the present genus and species was found, according 

 to Professor Marsh, in the "middle Cretaceous of Wyoming." Marsh's original description 

 was as follows: 



Another new member of the Stegosauria, from a lower horizon in the Cretaceous, was discovered several years since in 

 Wyoming and is now in the Yale Museum. The skull is not known, but various portions of the skeleton were secured. One 



a Marsh's restoration, fig. 119, does not include the portion of the skull in front of the nasal horn; if this were added the disproportion 

 would be less marked. — R. S. L. 



