122 BULLETIN 89, UNITED STATES NATIONAL MUSEUM. 



at the base of the tail [Triceratops]." In general it bears a striking resemblance 

 to the dermal spine of IIopKtosaurus marshi shown in plate 30, and on the analogy 

 of the dermal armor of PolacantJius (fig. 72), to which Iloplitosaurus appears to 

 be closely allied, I would say that spines of the character of these would belong 

 to the armor in front of the sacrum over the middorsal region rather than to the 

 caudal series, the position assigned it by Hatcher. 



From available records I am unable to say anything of its association with 

 other bones in the field. Collected by J. B. Hatcher in Converse County, Wyoming. 

 Cat. No. 7243, a thickened subrhombic plate with heavy obtuse median ridge, 

 lower surface concave across the shortest diameter (pi. 31 , fig. 3). No other bones 

 or fragments associated. Collected by G. L. Wait at Dovetail Butte, about 1 mile 

 west from ranch of E. J. Sanford, Valentine, Fergus County, Montana. 



Cat. No. 7724, a single heavy curved plate resembling somewhat Wieland's 

 figure 4 (pi. 31, fig. 4). It was associated with fragments of dinosaur bones, but 

 none were sufficiently complete to be identified. Collected by A. L. Beekley in 



Carbon County (SE. J sec. 14, 

 T. 24 N., R. 84 W.), Wyoming. 

 From the Lance formation. 



Cat. No. 7726. Some half 

 dozen rounded and elliptical 

 plates with spinal node and 



Fig. 73.— Dermal spine of a Ceeatopsian? dinosaur. Cat. No. 5793, ndgecl IOrDlS (pi. 31, tig. ^J, 

 U.S.N.M. About t V Nat size, a, Side view; b, front view; c, top which undoubtedly pertain to 

 view. After Marsh. , I ,1 ^ 



the same species as those fig- 

 ured by Wieland in figure 5 of the article cited above. These were collected 

 by D. F. Hewett near Cody (NE. i sec. 23, T. 50 N., R. 100 W.), Big Horn County, 

 Wyoming. 



Nos. 7804-7805. Two pointed spine-like ossifications (A and B, fig. 1, pi. 31). 

 Collected by J. B. Hatcher in Converse County, Wyoming. From the Lance 



formation. 



RESTORATIONS OF STEGOSAURUS. 



Since Prof. O. C. Marsh pubhshed the first pictorial restoration of Stegosawms 

 ungulatus, in 1891, 1 there have appeared, from time to time, various pictures and 

 statuettes depicting the life appearance of this curious reptile. 



These show a considerable variety of interpretations and are of interest as 

 exhibiting the diverse opinions held regarding its probable appearance in the flesh 

 and especially as to the arrangement of the dermal armor. In plates 32 to 36 and 

 arranged in chronological order are some of the more striking of these restorations. 

 Some comments upon the more important structural differences displayed in these 

 restorations are given below. 



As mentioned above, Marsh made the first restoration of Stegosaurus shown here 

 in plate 32, upper figure. It was based upon the cotypes 2 of S. ungulatus (Nos. 1853 

 and 1858, Yale Museum), "while some other parts, especially of the dermal armor, 

 have been placed in accordance with the known position in Stegosaurus stenops " (No. 

 4934, U.S.N.M.). It will be observed that notwithstanding the positive evidence 



> Amer. Journ. Sci., vol. 42, 1891, pi. 9. - E. S. Lull, Amer. Journ. Sci., ser. 4, vol. 30, 1910, pp. 363-364. 



