340 O. C. Marsh—The Order Theropoda. 
PLATE XI, 
Figure 1.—Pelvis of Ceratosaurus nasicornis, Marsh; side view, seen from 
the left. 
Figure 2.—Pelvis of Allosaurus Fragilis, Mate; the same view. 
_ a, acetabulum ; 4, ilium ; és, ischium; p, pu 
Both figures are one-twelfth natural size. 
Figure 3.—Pubes of Celwrus agilis, Marsh. 
a, side view; 6, front view ; ¢, foot, or distal end; one-fourth natural size. 
PLATE XII. 
FiGuRE 1.—Bones of left fore leg of Allosaurus fragilis, Marsh. 
Figure 2.—Bones of left hind leg of Allosaurus fragilis. 
Both figures are one-twelfth natural size. 
PLATE XIII. 
Figure 1,—Cervical vertebra of Calurus fragilis, ee front view. 
la, side view; 10, transverse section of same vertebra 
FiguRE 2.—Dorsal vertebra of Celurus fragilis ; front view. 
2a, side view; 2b, transverse section of same. 
FiguRE 3.—Caudal vertebra of Celurus fragilis ; front view. 
gts side view; 20, ttanavers section of same; o anterior ; Pp, , posterior c, 
cavity; f, lateral. foramen ne, neural ca nal; codssified rib; s, neural 
spine; 2, anterior zygapop ie sis; 2’, posterior aygapophysts. 
All the figures are natural size. 
PLATE XIV. 
Figure 1}. —Left ilium of Creosawrus atrox, Marsh; seen from the left. 
FiguRE 2.—The same, seen from below; both one-tenth natural size. 
a, anterior, or pubic, articulation ; 6, posterior, or ischiadic, articulation. 
Figure 3.—Lumbar vertebra of Creosaurus atrox ; front view. 
Figure 4.—The same; side su — _ ee both one-sixth natura 
a, anterior articular face cular face; s, neural gree d, 
diapophysis; z, anterior neuen np eden zy gapophysis. 
