NO. 1666. 



OSTEOLOGY OF 0AMPT08AURV8—O1LMORE. 



293 



marshii"^ and later referred by him to the new genus IloplitosaurusJ' 

 Most of the elements preserved were inclosed in two large joieces of 

 rock. 



The distinctive characters shown by the ilia, sacrum, and pubis 

 appear to justify the establishing of a new species, for which I pro- 

 pose the name CaTnptosaurus depressus, the specific name being sug- 

 gested by the narrowness or depressed nature of the ilia. 



Specific characfc7's. — Ilium narr(nr with shallow acetabular and 



Fig. 45. — Anterior portion of right ilium of Campto.s,\urus depressus. Cat. No. 

 475.5, U.S.N.M. Holotype. | nat. size. From a photograph. 



narrow preacetdbular notches. Sacrals ankylosed. with rounded 

 ventral surfaces. Anterior end of pubis broad. 



Detailed description. — The ilium, of which a representation is given 

 in figs. 45 and 46, is characterized by its narrow, vertical depth. The 

 acetabular notch is very shallow and short, while the preacetabular 

 notch is narrow, due to the lower point of origin of the preacetabular 

 process and the more elevated direction of the pubic process, which, 

 in all other species is deflected more ventrally (see Plate 14). Com- 



FiG. 46. — Left ilium of Camptosaurus depkessus. Cat. No. 4753, U.S.N.M. Holotypb. 

 i NAT. size. Preacetabular process wanting, and the upper posterior portio.n 



IS CRUSHED DOWN SOMEWHAT FROM ITS NORMAL OUTLINE. FROM A PHOTOGRAPH. 



pared with the ilium of C. browni., its nearest ally, G. depressus ap- 

 pears to indicate a smaller form. The interval between the pre- and 

 post-acetabular notches is comparatively short, measuring 141 mm., 

 Avhile in C. broivni it is 204 mm. The vertical height of the left 

 ilium from the inferior border of the middle of the acetabulum, 

 allowing for slight crushing, is about 105 mm. As shown by the 

 anterior portion of the right ilium (see fig. 45), the long, curved 



« Proc. U. S. Nat. Mus., XXIII, 1901, p. 591, pis. xxiii, xxiv. 

 » Science, XVI, Sept. 12, 1902, p. 435. 



